吉村　倫一YOSHIMURA Tomokazuヨシムラ　トモカズ

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プロフィール情報

• 姓

  吉村, ヨシムラ

• 名

  倫一, トモカズ

学位

• 博士（工学）, 熊本大学

研究キーワード

• コロイド・界面化学

研究分野

• ナノテク・材料, 基礎物理化学
• ナノテク・材料, 機能物性化学
• ナノテク・材料, グリーンサステイナブルケミストリー、環境化学

経歴

• 2014年04月, 奈良女子大学研究院自然科学系化学領域 教授
• 2012年04月, 2014年03月, 奈良女子大学研究院自然科学系化学領域 准教授（組織変更による配置換）
• 2007年04月, 2012年03月, 奈良女子大学大学院人間文化研究科共生自然科学専攻 准教授（学校教育法改正に伴い、名称変更）（理学部化学科兼担）
• 2006年04月, 2007年03月, 奈良女子大学大学院人間文化研究科共生自然科学専攻 助教授（理学部化学科兼担）
• 2001年04月, 2006年03月, 東京理科大学理学部応用化学科 助手・講師

学歴

• 1998年04月, 2001年03月, 熊本大学大学院, 自然科学研究科, 生産科学専攻

所属学協会

• 日本中性子科学会, 9999年
• 高分子学会, 9999年
• 色材協会
• アメリカ化学会
• 日本油化学会, 9999年
• 日本化学会コロイドおよび界面化学部会, 9999年
• 日本化学会, 9999年

Ⅱ．研究活動実績

論文

• 査読あり, 英語, Colloid Surf. A, Adsorption and Aggregation Properties of Homogeneous Polyoxyethylene Alkyl Ether- and Ester-Type Nonionic Surfactants with Multi-Branched Double Chains, Shiho Yada; Yuiko Yoshioka; Masashi Ohno; Toshinari Koda; Tomokazu Yoshimura, 2022年09月05日, 648, 129247, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2022.129247

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• 英語, Langmuir, Effect of Spacer Structures on the Interfacial Adsorption and Micelle Properties of Quaternary Ammonium Salt-Based Gemini Surfactants, Tsukasa Morita; Shiho Yada; Tomokazu Yoshimura, 2022年01月11日, 38, 1, 156, 163, 研究論文（学術雑誌）, 10.1021/acs.langmuir.1c02297

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• その他, Langmuir, Adsorption and Aggregation Behavior of Mixtures of Quaternary-Ammonium-Salt-Type Amphiphilic Compounds with Fluorinated Counterions and Surfactants, Risa Kawai; Shiho Yada; Tomokazu Yoshimura, 2021年09月14日, 37, 38, 11330, 11337, 研究論文（学術雑誌）, 10.1021/acs.langmuir.1c01912

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• その他, Chemistry – A European Journal, Fine Tunable, Redox Active Octapalladium Chains Supported by Linear Tetraphosphines, Leading to Dynamically 1D Self‐Assembled Coordination Polymers, Tomoaki Tanase; Kanako Nakamae; Haruka Miyano; Yasuyuki Ura; Yasutaka Kitagawa; Shiho Yada; Tomokazu Yoshimura; Takayuki Nakajima, 2021年08月19日, 27, 47, 12078, 12103, 研究論文（学術雑誌）, 10.1002/chem.202101715

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• その他, Journal of Molecular Liquids, Layer Structure of Quaternary-Ammonium-Salt-type Amphiphilic Gemini and Trimeric Ionic Liquids, Risa Kawai; Shiho Yada; Tomokazu Yoshimura, 2021年08月, 336, 116459, 116459, 研究論文（学術雑誌）, 10.1016/j.molliq.2021.116459

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• 査読あり, 英語, ACS Omega, Maltotriose–Chlorin e6 Conjugate Linked via Tetraethyleneglycol as an Advanced Photosensitizer for Photodynamic Therapy. Synthesis and Antitumor Activities against Canine and Mouse Mammary Carcinoma Cells, A. Narumi; R. Rachi; H. Yamazaki; S. Kawaguchi; M. Kikuchi; H. Konno; T. Osaki; Y. Okamoto; X. Shen; T. Kakuchi; H. Kataoka; A. Nomoto; T. Yoshimura; S. Yano, Glycoconjugated chlorins represent a promising class of compounds that meet the requirements for the third-generation photosensitizer (PS) for photodynamic therapy (PDT). We have focused on the use of glucose (Glc) to improve the performance of the PS based on the Warburg effect-a phenomenon where tumors consume higher Glc levels than normal cells. However, as a matter of fact, Glc-conjugation has a poor efficacy in hydrophilic modification; thus, the resultant PS is not suitable for intravenous injection. In this study, a Glc-based oligosaccharide, such as maltotriose (Mal3), is conjugated to chlorin e6 (Ce6). The conjugation is assisted by two additional molecular tools, such as propargyl amine and a tetraethylene glycol (TEG) derivative. This route produced the target Mal3-Ce6 conjugate linked via the TEG spacer (Mal3-TEG-Ce6), which shows the required photoabsorption properties in the physiological media. The PDT test using canine mammary carcinoma (SNP) cells suggested that the antitumor activity of Mal3-TEG-Ce6 is extremely high. Furthermore, in vitro tests against mouse mammary carcinoma (EMT6) cells have been demonstrated, providing insights into the photocytotoxicity, subcellular localization, and analysis of cell death and reactive oxygen species (ROS) generation for the PDT system with Mal3-TEG-Ce6. Both apoptosis and necrosis of the EMT6 cells occur by ROS that is generated via the photochemical reaction between Mal3-TEG-Ce6 and molecular oxygen. Consequently, Mal3-TEG-Ce6 is shown to be a PS showing the currently desired properties., 2021年03月16日, 6, 10, 7023, 7033, 研究論文（学術雑誌）, 国際誌, 10.1021/acsomega.0c06316

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• 英語, Colloids Surf., A, Unique Interfacial Adsorption Behavior of a Hydroxy Group-Containing Amino Acid Surfactant, S. Yada; M. Wakizaka; H. Shimosegawa; H. Fujita; M. Yamada; Y. Matsue; T. Yoshimura, 2021年02月, 611, 125757, 125757, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2020.125757

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• 英語, JOURNAL OF OLEO SCIENCE, Micelle Formation of Monoammonium Glycyrrhizinate, Keisuke Matsuoka; Mamoru Arima; Yusuke Goto; Shiho Yada; Tomokazu Yoshimura, Monoammonium glycyrrhizinate is produced by the neutralization of glycyrrhizic acid from plant licorice with ammonia. In this study, the physicochemical properties of aqueous monoammonium glycyrrhizinate were investigated from the viewpoint of surface chemistry. The structure of the amphiphilic molecule is bola type, comprising two glucuronic acid moieties having two carboxylic acids groups and an aglycone part having a carboxylic acid at the opposite end of the molecule from the glucuronic acids. We found that the physicochemical properties of aqueous monoammonium glycyrrhizinate are dependent on the ionization of the carboxylic acid groups. The solubility of monoammonium glycyrrhizinate gradually increased above pH 4 in the buffer solution. The critical micelle concentration (CMC) and surface tension at the CMC (gamma CMC) of monoammonium glycyrrhizinate were determined by the surface tension method to be 1.5 mmol L-1 and 50 mN m-1 in pH 5 buffer and 3.7 mmol L-1 and 51 mN m-1 in pH 6 buffer, respectively. The surface tension gradually decreased with increasing concentration of monoammonium glycyrrhizinate in the pH 7 buffer, but the CMC was not defined by the curve. Light scattering measurements also did not reveal a clear CMC in the pH 7 buffer. The ionization of the carboxylic acid groups in the bola-type amphiphilic molecule with increasing pH is disadvantageous for micelle formation. Cryo-transmission electron microscopy showed that monoammonium glycyrrhizinate forms rod-like micelles in pH 5 buffer, and small angle X-ray scattering experiments confirmed that the average micellar structure was rod-like in pH 5 buffer. Thus, it was found that monoammonium glycyrrhizinate can form micelles only in weakly acidic aqueous solutions., 2021年, 70, 7, 911, 918, 研究論文（学術雑誌）, 10.5650/jos.ess21046

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• 査読あり, 英語, Molecules, Surface Adsorption Properties and Layer Structures of Homogeneous Polyoxyethylene-Type Nonionic Surfactants in Quaternary-Ammonium-Salt-Type Amphiphilic Gemini Ionic Liquids with Oxygen- or Nitrogen-Containing Spacers, R. Kawai; M. Niki; S. Yada; T. Yoshimura, The amphiphilic ionic liquids containing an alkyl chain in molecules form nano-structure in the bulk, although they also show surface activity and form aggregates in aqueous solutions. Although insights into the layer structures of ionic liquids were obtained using X-ray and neutron scattering techniques, the nanostructures of ionic liquids remain unclear. Herein, the surface adsorption and bulk properties of homogeneous polyoxyethylene (EO)-type nonionic surfactants (CxEO6; x = 8, 12, or 16) were elucidated in quaternary-ammonium-salt-type amphiphilic gemini ionic liquids with oxygen or nitrogen-containing spacers [2Cn(Spacer) NTf2; (Spacer) = (2-O-2), (2-O-2-O-2), (2-N-2), (2/2-N-2), (3), (5), or (6); n = 10, 12, or 14 for (2-O-2) and n = 12 for all other spacers] by surface tension, small- and wide-angle X-ray scattering, cryogenic transmission electron microscopy, and viscosity measurements. The surface tension of C12EO6 in 2Cn(Spacer) NTf2 with oxygen-containing spacers increased with increasing concentration of C12EO6, becoming close to that of C12EO6 alone, indicating that the amphiphilic ionic liquid adsorbed at the interface was replaced with CxEO6. In contrast, both 2Cn(Spacer) NTf2 with nitrogen-containing spacers and nonionic surfactants remained adsorbed at the interface at high concentrations. In the bulk, it was found that 2Cn(Spacer) NTf2 formed layer structures, in which the spacing depended on the alkyl chain length of CxEO6. These insights are expected to advance the practical applications of amphiphilic ionic liquids such as ion permeation, drug solubilization, and energy delivery systems., 2020年10月22日, 25, 21, 4881, 4881, 研究論文（学術雑誌）, 10.3390/molecules25214881

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• 査読あり, 英語, Pharmaceuticals, Novel Photosensitizer β-Mannose-Conjugated Chlorin e6 as a Potent Anticancer Agent for Human Glioblastoma U251 Cells, Y. Shinoda, K. Kujirai, K. Aoki, M. Morita, M. Masuda, L. Zhang, Z. Kaixin, A. Nomoto, T. Takahashi, Y. Tsuneoka, J. Akimoto, H. Kataoka, R. Rachi, A. Narumi, T. Yoshimura, S. Yano, Y. Fujiwara, A photosensitizer is a molecular drug for photodynamic diagnosis and photodynamic therapy (PDT) against cancer. Many studies have developed photosensitizers, but improvements in their cost, efficacy, and side effects are needed for better PDT of patients. In the present study, we developed a novel photosensitizer β-mannose-conjugated chlorin e6 (β-M-Ce6) and investigated its PDT effects in human glioblastoma U251 cells. U251 cells were incubated with β-M-Ce6, followed by laser irradiation. Cell viability was determined using the Cell Counting Kit-8 assay. The PDT effects of β-M-Ce6 were compared with those of talaporfin sodium (TS) and our previously reported photosensitizer β-glucose-conjugated chlorin e6 (β-G-Ce6). Cellular uptake of each photosensitizer and subcellular distribution were analyzed by fluorescence microscopy. β-M-Ce6 showed 1000× more potent PDT effects than those of TS, and these were similar to those of β-G-Ce6. β-M-Ce6 accumulation in U251 cells was much faster than TS accumulation and distributed to several organelles such as the Golgi apparatus, mitochondria, and lysosomes. This rapid cellular uptake was inhibited by low temperature, which suggested that β-M-Ce6 uptake uses biological machinery. β-M-Ce6 showed potent PDT anti-cancer effects compared with clinically approved TS, which is a possible candidate as a next generation photosensitizer in cancer therapy., 2020年10月16日, 13, 10, 316, 316, 研究論文（学術雑誌）, 国際誌, 10.3390/ph13100316

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• 査読あり, 英語, Colloids Surf.,A, Physicochemical and Solution Properties of Quaternary-Ammonium-Salt-type Amphiphilic Gemini Ionic Liquids with Spacers Containing Oxygen or Nitrogen, R. Kawai; M. Niki; S. Yada; T. Yoshimura, 2020年10月, 603, 125218, 125218, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2020.125218

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• 査読あり, 日本語, オレオサイエンス, ヒドロキシ基含有アミノ酸系界面活性剤, Tomokazu YOSHIMURA; Shiho YADA, 2020年09月, 20, 9, 425, 430, 研究論文（学術雑誌）, 10.5650/oleoscience.20.425

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• 査読あり, その他, Langmuir, Microstructural Characterization of Foam Formed by a Hydroxy Group-Containing Amino Acid Surfactant Using Small-Angle Neutron Scattering, Shiho Yada; Hiroshi Shimosegawa; Hiroya Fujita; Munehiro Yamada; Yukako Matsue; Tomokazu Yoshimura, 2020年07月14日, 36, 27, 7808, 7813, 研究論文（学術雑誌）, 10.1021/acs.langmuir.0c00791

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• 査読あり, 英語, Langmuir, Surface Adsorption and Bulk Properties of Surfactants in Quaternary-Ammonium-Salt-Type Amphiphilic Monomeric and Gemini Ionic Liquids, Risa Kawai; Shiho Yada; Tomokazu Yoshimura, 2020年05月19日, 36, 19, 5219, 5226, 研究論文（学術雑誌）, 10.1021/acs.langmuir.0c00541

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• 査読あり, 日本語, 色材協会誌, 四級アンモニウム塩系両親媒性イオン液体（総説）, 河合里紗,矢田詩歩,吉村倫一, 2020年03月20日, 93, 3, 91, 98, 研究論文（学術雑誌）, 10.4011/shikizai.93.91

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• 査読あり, 英語, Langmuir : the ACS journal of surfaces and colloids, Adsorption and Aggregation Properties of Gemini-Type Amphiphilic Dendrimers., Tomokazu Yoshimura; Nara-Karyn Kawano; Shiho Yada; Hiroki Iwase, Gemini-type amphiphilic dendrimers featuring two dodecyl chains and two poly(amidoamine) dendrons (2C12-2denGn, where n is the dendron (den) generation (G) number (1, 2, 3, 4, or 5)) were synthesized using ethylenediamine, alkyl bromide, and methyl acrylate. These gemini-type dendrimers were characterized by surface tension, pyrene fluorescence, static light scattering, and small-angle X-ray scattering. The results showed clear breakpoints in the surface tension versus concentration plots, which indicated adsorption at the air/water interface and micelle formation in solution despite the bulky dendron structure (e.g., generations 3 to 5), contrasting the behavior of conventional surfactants. The 2C12-2denGn dendrimers could be densely packed at the air/water interface owing to enhanced interaction between the dendrons and between the alkyl chains. Furthermore, these dendrimers formed spherical micelles at a concentration of 5.0 mmol dm-3 in solution (pH 9); the overall micelle size was not dependent on the generation number of the dendron, while as the generation number increased, the core radius of the micelle decreased, and the shell thickness of the micelle increased., 2020年01月21日, 36, 2, 563, 570, 研究論文（学術雑誌）, 国際誌, 10.1021/acs.langmuir.9b02506

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• 査読あり, 英語, J. Mol. Liq., Characterization and Solution Properties of Adamantane-Containing Quaternary-Ammonium-Salt-Type Amphiphilic Ionic Liquids, R. Kawai, S. Yada, T. Yoshimura, 2019年11月15日, 294, 111586, 研究論文（学術雑誌）, 10.1016/j.molliq.2019.111586

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• 査読あり, 日本語, 科学と工業（大阪工研協会）, 泡沫の新たな構造解析法（解説）, 泡沫の新たな構造解析法(解説), 2019年11月, 93, 374, 378, 研究論文（学術雑誌）
• 査読あり, 英語, Phys. Chem. Chem. Phys., Physicochemical and Solution Properties of Quaternary-Ammonium-Salt-Type Amphiphilic Trimeric Ionic Liquids, K. Risa, S. Yada, T. Yoshimura, 2019年10月23日, 21, 25065, 25071, 研究論文（学術雑誌）, 10.1039/C9CP05541J

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• 査読あり, 英語, J. Mol. Liq., Solubilization Ability of Star-Shaped Trimeric Quaternary Ammonium Bromide Surfactant, K. Matsuoka, N. Takahashi, S. Yada, T. Yoshimura, 2019年10月01日, 291, 111254, 研究論文（学術雑誌）, 10.1016/j.molliq.2019.111254

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• 査読あり, 英語, J. Oleo Sci., Superoxide Scavenging Activity of Gold, Silver, and Platinum Nanoparticles Capped with Sugar-based Nonionic Surfactants, K. Matsuoka, Y. Nakatani, T. Yoshimura, T. Akasaki, 2019年09月04日, 68, 9, 847, 854, 研究論文（学術雑誌）, 10.5650/jos.ess19079

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• 査読あり, 英語, ACS Omega, Characterization and Solution Properties of Quaternary-Ammonium-Salt-Type Amphiphilic Gemini Ionic Liquids, R. Kawai, S. Yada, T. Yoshimura, 2019年08月20日, 4, 10, 14242, 14250, 研究論文（学術雑誌）, 10.1021/acsomega.9b01660

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• 査読あり, 英語, J. Mol. Liq., Adsorption and Aggregation Properties of Alkoxy-Group-Modified Homogeneous Polyoxyethylene Alkyl Ether Nonionic Surfactants, S. Yada, T. Suzuki, S. Hashimoto, T. Yoshimura, 2019年06月15日, 284, 586, 591, 研究論文（学術雑誌）, 10.1016/j.molliq.2019.03.161

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• 査読あり, 英語, Acc. Mater. Surf. Res.（材料表面）, 環境負荷の低減を目指した非イオン界面活性剤の開発, 矢田詩歩,吉村倫一, 2019年04月27日, 4, 2, 69, 8, 研究論文（学術雑誌）
• 査読あり, 英語, Langmuir, Structure and Catalytic Activities of Gold Nanoparticles Protected by Homogeneous Polyoxyethylene Alkyl Ether Type Nonionic Surfactants, S. Yada; T. Yoshimura, 2019年04月16日, 35, 15, 5241, 5249, 研究論文（学術雑誌）, 10.1021/acs.langmuir.9b00142

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• 査読あり, 英語, J. Colloid Interface Sci., Rheo-SANS Study on Relationship between Micellar Structures and Rheological Behavior of Cationic Gemini Surfactants in Solution, H. Iwase, R. Kawai, K. Morishima, S. Takata, T. Yoshimura, M. Shibayama, Hypothesis: Gemini surfactant 12-2-12 (dimethylene-1,2-bis(dodecyl dimethylammonium bromide)) solutions are known to show shear thickening and thinning under salt-free conditions. Because the rheological behavior of the wormlike micelles formed by 12-2-12 in solution is related to their structure, we expected that changes to the precursor structure would affect their rheological behaviors. It is also important to understand the effect of the introduction of a spacer group in the 12-2-12 molecules on the rheological behavior and structure of the wormlike micelles under shear flow.Experiments: Simultaneous small-angle neutron scattering and rheological measurements (Rheo-SANS) of the 12-2-12 solutions were performed. We exhaustively studied the structural changes in the wormlike micelles upon increasing shear rate.Findings: We found that the wormlike micelles were oriented in the direction of the flow due to elongation and that changes to the precursor of the wormlike micelles did not affect the shear thickening. As a precursor structural change of shear thinning, the wormlike micelles elongated while maintaining their orientation. We found that an increase in the molecular curvature of the 12-2-12 due to the introduction of a spacer-group contributed to the unusual rheological behaviors of the wormlike micelles in a solution under shear flow. (C) 2018 Elsevier Inc. All rights reserved., 2019年03月07日, 538, 357, 366, 研究論文（学術雑誌）, 10.1016/j.jcis.2018.11.104

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• 査読あり, 英語, Colloids Surf.,A, Emulsification, Solubilization and Detergency Behaviors of Homogeneous Polyoxypropylene-Polyoxyethylene Alkyl Ether Type Nonionic Surfactants, S. Yada, K. Matsuoka, Y. Nagai-Kanasaki, K. Gotoh, T. Yoshimura, 2019年03月05日, 564, 51, 58, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2018.12.030

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• 査読あり, 日本語, 月刊ファインケミカル（シーエムシー出版）, 四級アンモニウム塩系両親媒性イオン液体の開発（特集「イオン液体の開発と応用展開」）, 河合里紗,吉村倫一, 2018年09月15日, 47, 9, 5, 13, 研究論文（学術雑誌）
• 査読あり, 英語, Journal of Molecular Liquids, Solubilization ability of N,N-dimethyl-N-alkyladamantylammonium bromide, Keisuke Matsuoka; Rinpei Omori; Shiho Yada; Tomokazu Yoshimura; Hiroki Iwase, Adamantane is difficult to dissolve in water owing to its bulky steric hydrocarbon structure. We designed a novel amphiphilic molecule by introducing an alkyl chain and a cation group into an adamantyl group. N,N-dimethyl-N-alkyladamantylammonium bromide (CnAdAB n is the alkyl chain length, where n = 10, 12, and 14) dissolves easily in water by forming micelles above the critical micelle concentration. Aggregates of this surfactant series form small nonspherical micelles several nanometers in size with relative small aggregation number 53 (n = 10), 59 (n = 12), and 63 (n = 14) at the typical concentration. Small-angle X-ray scattering measurement showed that the micellar structure of C12AdAB was changed slightly by solubilization of naphthalene and stearic acid. Moreover, the solubilization ability of the aggregates was studied using naphthalene and long-alkyl-chain fatty acids (myristic, palmitic, and stearic acids). The same solubilization experiments were performed using typical cationic surfactants (dodecyltrimethylammonium bromide and a gemini surfactant) for comparison. The molar solubilization ratios indicate that the CnAdAB series can solubilize the aromatic compound naphthalene as well as the other surfactants, whereas they can barely solubilize the long-alkyl-chain fatty acids. The solubilization stability can be analyzed by estimating the Gibbs free energy change (ΔG0) for the transfer of solubilizate molecules to the aggregate phase. The gemini surfactant system showed the largest negative value of ΔG0 for both naphthalene and the fatty acids. On the other hand, solubilization of fatty acids into CnAdAB micelles was not advantageous energetically. These results indicate that the solubilization ability of CnAdAB surfactants is not generally suitable for solubilization of long-alkyl-chain fatty acids owing to the smallness of the micelles., 2018年06月15日, 260, 131, 137, 研究論文（学術雑誌）, 10.1016/j.molliq.2018.03.078

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• 査読あり, 日本語, Colloid & Interface Communication, 分岐2鎖型界面活性剤の水溶液物性に及ぼす親水基と疎水鎖の影響, 吉岡優惟子,矢田詩歩,ヨシムラ, 2018年05月10日, 43, 2, 40, 43, 研究論文（学術雑誌）
• 査読あり, 英語, Journal of Molecular Liquids, Adsorption dynamics of homogeneous polyoxypropylene-polyoxyethylene alkyl ether nonionic surfactants at the air/water interface, Shiho Yada; Toshiyuki Suzuki; Satoru Hashimoto; Tomokazu Yoshimura, The dynamic surface tensions of two homogeneous polyoxyethylene (EO) alkyl ether nonionic surfactants with terminal hydroxy group (C12EOx, where C12 is a dodecyl chain and x is the length of the EO chain x = 6, 8) and two homogeneous polyoxypropylene-polyoxyethylene (PO-EO) alkyl ether nonionic surfactants (C12EOxPO3, where PO3 is a trioxypropylene chain inserted between the EOx and the terminal hydroxy group) were measured using the maximum bubble pressure method. The effects of EO chain length, the presence or absence of the PO3 chain, and the surfactant concentration on the maximum rates of surface-tension reduction and diffusion coefficient were investigated. The C12EO6PO3 surfactant exhibited the fastest rate of surface-tension reduction of the four systems studied, despite its complex hydrophobic-alkyl-chain/hydrophilic-EO-chain/hydrophobic-PO-chain structure that differs from that of conventional EO alkyl ether surfactants. The diffusion coefficients obtained from short and long time analyses indicate that surfactant diffusion to the subsurface is faster for the C12EOxPO3 surfactants than the C12EOx surfactants (short time data), while surfactant adsorption from the subsurface to the air/water interface is faster for the C12EOx surfactants than the C12EOxPO3 surfactants (long time data)., 2018年04月01日, 255, 208, 214, 研究論文（学術雑誌）, 10.1016/j.molliq.2018.01.150

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• 査読あり, 日本語, 塗装工学, 各種産業分野への利用を目指した新規界面活性剤の開発（解説）, 吉村倫一, 2018年04月, 53, 4, 122, 130, 研究論文（学術雑誌）
• 査読あり, 日本語, 化学工業, 単一鎖長ポリオキシプロピレン－ポリオキシエチレン系非イオン界面活性剤の開発（解説）, 矢田詩歩,吉村倫一, 2018年02月01日, 69, 2, 41, 46, 研究論文（学術雑誌）
• 査読あり, 英語, Colloids Surf., A, Tadpole-Type Amphiphilic Dendrimers with Bulky Dendrons: Adsorption and Aggregation Properties, T. Yoshimura, A. Ebihara, H. Iwase, 2017年11月20日, 533, 197, 203, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2017.08.010

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• 査読あり, 英語, J. Oleo Sci., Dynamic Surface Tension of Heterogemini Surfactants with Quaternary Ammonium Salt and Gluconamide or Sulfobetaine Headgroups, T. Yoshimura, K. Nyuta, 2017年10月01日, 66, 10, 1139, 1147, 研究論文（学術雑誌）, 10.5650/jos.ess17021

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• 査読あり, 英語, Langmuir, Structure and Rheology of Wormlike Micelles Formed by Fluorocarbon-Hydrocarbon-Type Hybrid Gemini Surfactant in Aqueous Solution, K. Morishima, S. Sugawara, T. Yoshimura, M. Shibayama, 2017年06月20日, 33, 24, 6084, 6091, 研究論文（学術雑誌）, 10.1021/acs.langmuir.7b00902

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• 査読あり, 英語, Colloid Polym. Sci., Single-Alkyl and Multi-Alkyl Chain-Containing Amphiphilic Oligomers with Several Sugar Side Chains: Solution Properties and Nano-Structural Analysis of Aggregates by SANS, T. Yoshimura, Y. Nakatani, K. Matsuoka, K. Akutsu, H. Iwase, 2017年05月, 295, 5, 793, 802, 研究論文（学術雑誌）, 10.1007/s00396-017-4063-3

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• 査読あり, 英語, Langmuir, Adsorption and Aggregation Properties of Homogeneous Polyoxypropylene-Polyoxyethylene Alkyl Ether Type Nonionic Surfactants, S. Yada, T. Suzuki, S. Hashimoto, T. Yoshimura, 2017年04月18日, 33, 15, 3794, 3801, 研究論文（学術雑誌）, 10.1021/acs.langmuir.7b00104

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• 査読あり, 英語, J. Oleo Sci., Synthesis and Solution Properties of Adamantane-Containing Quaternary Ammonium Salt-type Cationic Surfactants: Hydrocarbon-based, Fluorocarbon-based and Bola-type, T. Yoshimura, M. Okada, K. Matsuoka, 2016年10月01日, 65, 10, 843, 852, 研究論文（学術雑誌）, 10.5650/jos.ess16095

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• 査読あり, 英語, Colloids Surf., A, Aggregate Formation of Glycyrrhizic Acid, K. Matsuoka, R. Miyajima, Y. Ishida, S. Karasawa, T. Yoshimura, Glycyrrhizic acid is derived from the licorice root. The compound is amphiphilic with a large hydrophobic aglycone group, and two glucuronic acids and a carboxyl group constituting the hydrophilic part. Therefore, glycyrrhizic acid can form aggregates or lower the surface tension of aqueous solutions owing to its specific amphiphilic structure. The aqueous solubility of glycyrrhizic acid is relatively low (0.15 mM) and dependent on the solvent pH due to the weak acidity resulting from the carboxylic groups. Glycyrrhizic acid is quite soluble in a buffer solution at pH 4.5, and its ability to affect the surface tension of the buffer solution increases from pH 5. The critical micelle concentration (cmc) was estimated to be 2.9 mM (gamma(CMC) = 55.2 mN/m) and 5.3 mM (gamma(CMC) = 56.8 mN/m) at pH 5 and 6, respectively. The surface tension also decreased gradually at pH 7, but the critical point was not observed in the curve. At pH 7, the pyrene fluorescent probe method and light scattering measurements did not show a clear cmc. Small angle X-ray scattering experiments revealed that the aggregates were rod-like micelles with an estimated radius and length of 1.5 nm and 21 nm, respectively, at 5 mM in a pH 5 solvent. Transmission electron microscopy confirmed that glycyrrhizic acid forms rod-like micelles. These results suggest that glycyrrhizic acid has potential applications as a biosurfactant in various fields. (C) 2016 Elsevier B.V. All rights reserved., 2016年07月05日, 500, 112, 117, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2016.04.032

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• 査読あり, 英語, Colloids Surf., A, Structural Study on Aggregation Behavior of Star-type Trimeric Surfactant in the presence of sodium salicylate, T. Kusano, K. Akutsu, H. Iwase, T. Yoshimura, M. Shibayama, We investigated the aggregation behavior of star-type trimeric surfactants (3C(12)trisQ) with a hydrocarbon chain length (n) of 12 in sodium salicylate (NaSal) aqueous solution at various surfactant (C-D) and salt concentrations (C-S) using small-angle X-ray scattering (SAXS) and rheological measurements. At a low surfactant concentration (C-D = 7 mM), 3C(12)trisQ aggregates in solution evolved from ellipsoidal micelles, to rodlike or wormlike micelles and finally to multi-lamellar vesicles (MLVs) with increasing C-S. In contrast, at higher surfactant concentrations (C-D =14 and 28 mM), we did not observe vesicle formations of 3C(12)trisQ because 3C(12)trisQ were insoluble in solution at higher NaSal concentrations. The structural transitions of the 3C(12)trisQ aggregates strongly depended on both C-S and C-D. We also compared the MLV structure formed by 3C(12)trisQ with that formed by gemini-type surfactants (12-2-12). The repeat distance of the 3C(12)trisQ MLV (33.95 angstrom) was remarkably larger than that of the 12-2-12 (22.36 angstrom). We found that introducing spacer chains, i.e., from dimeric to trimeric surfactants, caused a decrease in NaSal concentrations at which micelle-to-vesicle transitions were observed. (C) 2016 Elsevier B.V. All rights reserved., 2016年05月20日, 497, 109, 116, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2016.02.041

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• 査読あり, 英語, J. Oleo Sci., Solution Properties of Dissymmetric Sulfonate-type Anionic Gemini Surfactants, T. Yoshimura, K. Akiba, Dissymmetric and symmetric anionic gemini surfactants, N-alkyl-N'-alkyl-N,N'dipropanesulfonylethylenediamine (C,CSul, where in and n represent alkyl chain lengths of m-n = 4-16, 6-14, 8-12, 10-10, and 12-12), were synthesized by two-or three-step reactions. Their physicochemical properties were characterized by equilibrium surface tension measurements, steady-state fluorescence spectroscopy of pyrene, and dynamic light scattering. The critical micelle concentration (CMC) of the dissymmetric surfactants C(4)C(16)Sul, C(6)C(14)Sul, and C(8)C(12)Sul was slightly lower than that of the symmetric surfactant C C(1)C(10)Sul. The occupied area per molecule (A) of C(8)C(12)Sul was smaller than that of C(10)C(10)Sul, indicating that C(8)C(12)Sul has a high surface activity. However, the increase in the degree of dissymmetry from C(8)C(12)Sul to C(6)C(14)Sul and then to C(4)C(16)Sul resulted in high surface tension and large A. Based on the surface tension, the standard free energies of micellization (Delta G degrees (mic)) and adsorption (Delta G degrees (ads)), the efficiency of surface adsorption (pC), and the effectiveness of surface adsorption (CMC/C-20) were obtained. These parameters suggested that C(8)C(12)Sul formed micelles more readily than the other surfactants. The properties determined from the surface tension indicated that C(8)C(12)Sul's ability is intermediate between those of C(10)C(10)Sul and C(12)C(12)Sul. The pyrene fluorescence and dynamic light scattering results revealed that the micelle size depends on the longer of the two alkyl chains in dissymmetric surfactants., 2016年02月01日, 65, 2, 135, 141, 研究論文（学術雑誌）, 10.5650/jos.ess15237

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• 査読あり, 英語, Colloids Surf., A, Solubilization of Naphthalene and Octafluoronaphthalene in Ionic Hydrocarbon and Fluorocarbon Surfactants, K. Matsuoka, R. Yamashita, M. Ichinose, M. Kondo, T. Yoshimura, The solubilization abilities of various kinds of surfactants are clarified through a systematic solubilization study. Naphthalene and octafluoronaphthalene have similar molecular structures and can be used as solubilizates in hydrocarbon and fluorocarbon surfactant systems. The solubilizaton quantities are measured for typical anionic, cationic, and cationic gemini surfactants with different alkyl chain lengths (nine hydrocarbon and six fluorocarbon surfactants). The maximum solubilization quantities of naphthalene and octafluoronaphthalene in aqueous solutions of hydrocarbon or fluorocarbon surfactant are measured as a function of surfactant concentration at 318.2 K. There are four solubilization systems regarding hydrocarbons and fluorocarbons. Judging from the molar solubilization ratio (MSR), naphthalene is solubilized most in typical gemini surfactant solution (12-2-12), whereas hardly any naphthalene is solubilized in fluorocarbon surfactants. On the other hand, the maximum MSR of octafluoronaphthalene is found for the gemini type of fluorocarbon surfactant, whereas the minimum value is recorded in the C9H19COONa system. Therefore, gemini surfactants reveal excellent solubilization abilities in homogeneous combination systems. The solubilization stability can be analyzed by estimating the Gibbs free energy change (Delta G degrees) for the transfer of solubilizate molecules to the aggregate phase. The largest negative value of Delta G degrees is estimated to be -34.8 kJ mol(-1) for the homogeneous system of octafluoronaphthalene and the gemini-type fluorocarbon surfactant, whereas smaller values are obtained for the heterogeneous systems of naphthalene and fluorocarbon surfactants. These results indicate that fluorocarbon surfactants are not generally suitable for the solubilization of naphthalene. (C) 2014 Elsevier B.V. All rights reserved., 2014年08月20日, 456, 83, 91, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2014.04.060

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• 査読あり, 日本語, 色材協会誌, 高性能化・高機能化を目指した両親媒性デンドリマーの開発（解説）, 吉村倫一, 2014年05月20日, 87, 5, 158, 164, 研究論文（学術雑誌）
• 査読あり, 日本語, 顕微鏡, 日本顕微鏡学会, クライオ電子顕微鏡による界面活性剤ミセルのナノ構造観察（特集：大気圧走査電子顕微鏡（ASEM））, 吉村倫一,小川哲也, 2014年05月, 49, 1, 22, 25, 研究論文（学術雑誌）

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• 査読あり, 日本語, フレグランス ジャーナル, フレグランスジャーナル社, 新規天然機能性素材として乳酸菌発酵米を用いたエマルションの開発（特集）, 吉村倫一,羽田容介,澤木茂豊, 2014年05月, 42, 5, 41, 45, 研究論文（学術雑誌）

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• 査読あり, 英語, JOURNAL OF OLEO SCIENCE, Adsorption and Aggregation Properties of Multichain Anionic Amphiphilic Oligomers Consisting of Dodecyl Acrylamide and Sodium Acrylate, Tomokazu Yoshimura; Hiroaki Yoshida; Kunio Esumi, Multichain amide-bonded anionic amphiphilic oligomers consisting of dodecyl acrylamide and sodium acrylate (i.e., xC(12)AAm-yAA, where x and y represent the number of dodecyl acrylamide (C(12)AAm) and sodium acrylate (AA) units, respectively) were synthesized via the radical oligomerization of two monomers in the presence of 2-aminoethanethiol hydrochloride. Equilibrium and dynamic surface tension, pyrene fluorescence, dynamic light scattering, and steady-state fluorescence quenching measurements were used to characterize the properties of the oligomers. In addition, the effects of the polymerization degree and number of dodecyl chains and hydrophilic groups on these properties were evaluated via comparison of these results with those of previously reported amphiphilic oligomers with ester bonds and conventional anionic monomeric surfactants. xC(12)AAm-yAA exhibits lower critical micelle concentration (cmc) values than conventional sodium n-dodecanoate surfactant, indicating their excellent micelle-forming ability despite the large molecular structure with a long polymer main chain. The 3.0C(12)AAm-7.5AA oligomer features the lowest cmc. The surface tensions of xC(12)AAm-yAA at the cmc are lower than those of the conventional surfactant, which indicates that the oligomers adsorb and orient efficiently at the air-water interface. Further, xC(12)AAm-yAA forms small aggregates with diameters of similar to 10 nm and aggregation numbers of 2-8 as well as large aggregates composed of masses of small aggregates. An increase in the polymerization degree of the oligomers decreases the aggregation number of the small aggregates; this indicates that it is more difficult for oligomers with long polymer chains to form aggregates due to their bulky structure., 2013年09月, 62, 9, 673, 680, 研究論文（学術雑誌）, 10.5650/jos.62.673

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• 査読あり, 英語, Journal of Oleo Science, Japan Oil Chemists' Society, Solution Properties of Amphiphilic Telomers with Multiple Sugar Chains and Terminal Alkyl Chain, 吉村倫一, Amphiphilic telomers with multiple sugar chains and a terminal undecyl or heptadecyl chain (i.e., C_nAm-mGEMA, where n and m represent alkyl chain lengths of 11 or 17 with a degree of polymerization of 2.0 or 3.0 for glucosyloxyethyl methacrylate (GEMA) units, respectively) were synthesized via monomeric radical telomerization in the presence of 2-aminoethanethiol hydrochloride. Surface tension, pyrene fluorescence, and dynamic light scattering were measured to characterize the solution properties of the synthesized telomers. In addition, the effects of alkyl chain length and degree of polymerization of hydrophilic GEMA units on the measured properties were evaluated by comparison with those of conventional polyoxyethylene dodecyl ether nonionic surfactants. C_nAm-mGEMA telomers exhibited higher critical micelle concentration (CMC) values than polyoxyethylene dodecyl ether surfactants with similar number of hydrophilic groups did. The synthesized telomers are highly efficient in reducing the surface tension of water, despite the relatively large hydrophilic structures within the sugar units (GEMA). A unique behavior was observed in that adsorption at the air-water interface and solution aggregation occurred simultaneously at a concentration below CMC (as determined by the surface tension method). This suggests that aggregate formation occurs readily in solution along with the adsorption at the interface because of strong attractive interactions between multiple sugar GEMA chains. Further, aggregates formed by C_nAm-mGEMA telomers differ depending on the number of sugar chains, i.e., an increase in the degree of polymerization of the telomers increases the size of the aggregates. This indicates that it is easier for telomers with more sugar GEMA chains to form large aggregates due to the interactions between their hydroxyl groups., 2013年08月, 62, 8, 571-577, 577, 10.5650/jos.62.571

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• 査読あり, 英語, JOURNAL OF OLEO SCIENCE, Solution Properties and Emulsification Properties of Amino Acid-Based Gemini Surfactants Derived from Cysteine, Tomokazu Yoshimura; Ayako Sakato; Kunio Esumi, Amino acid-based anionic gemini surfactants (2C(n)diCys, where n represents an alkyl chain with a length of 10, 12, or 14 carbons and "di" and "Cys" indicate adipoyl and cysteine, respectively) were synthesized using the amino acid cysteine. Biodegradability, equilibrium surface tension, and dynamic light scattering were used to characterize the properties of gemini surfactants. Additionally, the effects of alkyl chain length, number of chains, and structure on these properties were evaluated by comparing previously reported gemini surfactants derived from cystine (2C(n)Cys) and monomeric surfactants (C(n)Cys). 2C(n)diCys shows relatively higher biodegradability than does C(n)Cys and previously reported sugar-based gemini surfactants. Both critical micelle concentration (CMC) and surface tension decrease when alkyl chain length is increased from 10 to 12, while a further increase in chain length to 14 results in increased CMC and surface tension. This indicates that long-chain gemini surfactants have a decreased aggregation tendency due to the steric hindrance of the bulky spacer as well as premicelle formation at concentrations below the CMC and are poorly packed at the air/water interface. Formation of micelles (measuring 2 to 5 nm in solution) from 2C(n)diCys shows no dependence on alkyl chain length. Further, shaking the mixtures of aqueous 2C(n)diCys surfactant solutions and squalane results in the formation of oil-in-water type emulsions. The highly stable emulsions are formed using 2C(12)diCys or 2C(14)diCys solution and squalane in a 1:1 or 2:1 volume ratio., 2013年08月, 62, 8, 579, 586, 研究論文（学術雑誌）, 10.5650/jos.62.579

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• 査読あり, 英語, JOURNAL OF OLEO SCIENCE, Equilibrium Surface Tension, Dynamic Surface Tension, and Micellization Properties of Lactobionamide-Type Sugar-Based. Gemini Surfactants, Tomokazu Yoshimura; Shin Umezawa; Akihiko Fujino; Kanjiro Torigoe; Kenichi Sakai; Hideki Sakai; Masahiko Abe; Kunio Esumi, A sugar-based gemini surfactant N,N'-dialkyl-N,N'-dilactobionamideethylenediamine (2C(n)Lac, where n represents alkyl chain lengths of 8, 10, 12, and 14) was synthesized by reacting N,N'-dialkylethylenediamine with lactobionic acid. The adsorption properties of 2C(n)Lac were characterized by equilibrium and dynamic surface tension measurements. Their micellization properties were investigated by steady-state fluorescence using pyrene as a probe and dynamic light scattering (DLS) techniques. The dependence of these properties on the alkyl chain length and the number of sugars was determined through a comparison with the corresponding monomeric surfactants C(n)MLA and previously reported sugar-based gemini surfactants containing monosaccharide gluconamide or disaccharide lactobionamide groups with a hexanediamide spacer. The critical micelle concentration (cmc) and surface tension of 2C(n)Lac are both lower than those of C(n)MLA surfactants. These lower values indicate that the synthesized sugar-based gemini surfactants have excellent micelle-forming ability in solution and high adsorption ability at the air-water interface, which result from strong interactions of the hydrogen bonds between the hydroxyls in lactobionamide groups. When the alkyl chain length of 2C(n)Lac increases to 14, premicellar formation occurs in the solution along with adsorption at the air-water interface at concentrations below the cmc. Furthermore, 2C(n)Lac forms micelles measuring 4 to 12 nm in solution, with no dependence on the alkyl chain length, and their size slightly increases with increasing concentration., 2013年06月, 62, 6, 353, 362, 研究論文（学術雑誌）, 10.5650/jos.62.353

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• 査読あり, 英語, JOURNAL OF OLEO SCIENCE, Solution Properties of Tadpole-type Cationic Amphiphilic Dendrimers Consisting of an Alkyl Chain, a Quaternary Ammonium, and a Poly(amidoamine) Dendron, Tomokazu Yoshimura; Masanori Saito; Kunio Esumi, Tadpole-type amphiphilic dendrimers consisting of an alkyl chain, a quaternary ammonium bromide (qb) and a poly(amidoamine) dendron (den) (C(n)qbdenGm, where n represents an alkyl chain with a length of 10,14, or 18 carbons; in is the generation number G of dendron taking the value - 0.5, 0.5, or 1.5) were synthesized using N,N-dimethylethylenediamine as a central scaffold. Electrical conductivity, surface tension, pyrene fluorescence, and dynamic light scattering measurements were used to characterize the properties of the dendrimers. In addition, the effect of the alkyl chain length and the generation number of a dendron on these properties was evaluated through a comparison with those of the corresponding previously reported amphiphilic dendrimers with lactobionamide sugar terminal groups (C(n)qbdenGmLac) and conventional cationic monomeric surfactants (C(n)TAB). Both critical micelle concentration (cmc) and surface tension (except for C-18 series) were lower than those of C(n)qbdenGmLac and C(n)TAB with the same alkyl chain length, indicating that the synthesized amphiphilic dendrimers have an excellent micelle-forming ability in solution and high adsorption ability at the air/water interface, in spite of the large bulky dendron structure. When the alkyl chain length and the generation number of the amphiphilic dendrimers were increased, the surface tension became high because of the curved long alkyl chain and the bulky structure of dendron. Further, C(n)qbdenGm formed micelles with a small size in solution, and the micelles of C(n)qbdenG(-0.5) had almost a constant size despite the changes in the concentration, while those of C(n)qbdenG0.5 and C(n)qbdenG1.5 became smaller with increasing concentration. The difference in the behavior results from the difference in the number of amide groups in the low- and high-generation dendrons., 2013年04月, 62, 4, 213, 221, 研究論文（学術雑誌）, 10.5650/jos.62.213

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• 査読あり, 英語, JOURNAL OF OLEO SCIENCE, Unique Solution Properties of Quaternized Oligomeric Surfactants Derived from Ethylenediamine or G0 Poly (amidoamine) Dendrimers, Tomokazu Yoshimura; Shunsuke Abe; Kunio Esumi, New quaternized oligomeric surfactants containing 4 or 8 alkyl chains were synthesized using ethylenediamine or poly(amidoamine) dendrimers as the central scaffold. Electrical conductivity, surface tension, and pyrene fluorescence measurements, as well as dynamic light scattering were used to characterize their properties. In addition, the dependence of these properties on the alkyl chain length, number of chains, and dendrimer generation was determined through comparison with previously reported oligomeric surfactants. The relation between surface tension and concentration for the oligomeric surfactants exhibited clear breakpoints, which reflect the critical micelle concentration (cmc). Both cmc and surface tension were lower than those of monomeric alkyltrimethylammonium bromide surfactants, indicating that the synthesized oligomeric surfactants have excellent micelle-forming ability in solution and high adsorption ability at the air/water interface, in spite of the large bulky structure containing multiple alkyl chains and headgroups within one molecule. When the alkyl chain length or the number of chains of the oligomeric surfactants was increased, a unique behavior was observed in that adsorption at the air/water interface and solution aggregation occurred simultaneously at a concentration below cmc (as determined by the surface tension method). This suggests that aggregate formation occurs readily in solution along with the adsorption at the interface because of strong attractive interactions between multiple alkyl chains., 2012年12月, 61, 12, 699, 706, 研究論文（学術雑誌）, 10.5650/jos.61.699

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• 査読あり, 英語, LANGMUIR, Structural and Rheological Studies on Growth of Salt-Free Wormlike Micelles Formed by Star-Type Trimeric Surfactants, Takumi Kusano; Hiroki Iwase; Tomokazu Yoshimura; Mitsuhiro Shibayama, We investigated the growth mechanisms of wormlike micelles formed by star-type trimeric surfactant (3C(12)trisQ) with a hydrocarbon chain length of 12 in an aqueous solution. A 3C(n)trisQ molecule consists of three hydrocarbon chains and three hydrophilic groups connected by spacer chains, where n is the carbon number in the hydrocarbon chain. Our recent studies showed that the aggregates formed by 3C(12)trisQ exhibited sphere-to-rod transition and the growth of wormlike micelles in an aqueous solution in the absence of salt. We performed small-angle neutron scattering (SANS) and rheological measurements and investigated the aggregation behavior of 3C(12)trisQ with various surfactant volume fractions. All SANS profiles for the 3C(12)trisQ indicated peak-profiles in the q range of 0.02 angstrom(-1) < q <0.05 angstrom(-1), where the magnitude of the scattering vector q is defined by q = 4 pi sin(theta/2)/lambda (lambda and theta represent the wavelength and scattering angle, respectively). These peaks were attributed to repulsive interparticle interactions between the micelles. The volume fraction dependence of the SANS peak-position was in agreement with the rheological behavior. These results suggest that 3C(12)trisQ shows sphere-to-rod transition and can produce wormlike micelles in the absence of salt. To determine the structural parameters quantitatively, model-fitting analysis was performed using a charged cylindrical or charged ellipsoidal particle scattering function. The radius, length, and number of water molecules per surfactant molecule (n(w)) inside the micelles were evaluated. The length increased and the n(w), value decreased with increasing phi, indicating that the growth of a wormlike micelle accompanies the extrusion of water from the micelle. The end-cap energies of star-type trimeric, gemini, and monomeric surfactants were evaluated from phi dependence of zero-shear viscosity. We found that wormlike micelles formed by 3C(12)trisQ exhibited a higher end-cap energy than gemini surfactant., 2012年12月, 28, 49, 16798, 16806, 研究論文（学術雑誌）, 10.1021/la304275h

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• 査読あり, 日本語, 色材協会誌, Japan Society of Colour Material, 第四級アンモニウム塩を有するトリメリック型カチオン界面活性剤（総説）, 吉村倫一, 近年，著者らは，研究例の少ない分子内に3本のアルキル鎖と3つの四級アンモニウム基を含むトリメリック型界面活性剤に着目して研究を行ってきた。本稿では，トリス（2-アミノエチル）アミンを連結基に有する星型のトリメリック型カチオン界面活性剤を中心に，エチレン，プロピレンなどの柔軟な連結基およびtrans-ブテニレン，m-，p-キシリレンなどの剛直な連結基を有する直鎖型のトリメリック型界面活性剤の合成，臨界ミセル濃度や表面張力などの物性，水溶液中で形成するミセルのナノ構造について紹介する。, 2012年09月, 85, 9, 370-377, 377, 10.4011/shikizai.85.370

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• 査読あり, 英語, LANGMUIR, Star-Shaped Trimeric Quaternary Ammonium Bromide Surfactants: Adsorption and Aggregation Properties, Tomokazu Yoshimura; Takumi Kusano; Hiroki Iwase; Mitsuhiro Shibayama; Tetsuya Ogawa; Hiroki Kurata, Novel star-shaped trimeric surfactants consisting of three quaternary ammonium surfactants linked to a tris(2-aminoethyl)amine core were synthesized. Each ammonium had two methyls and a straight alkyl chain of 8, 10, 12, or 14 carbons. The adsorption and aggregation properties of these tris(N-alkyl-N,N-dimethyl-2-ammoniumethyl)amine bromides (3C(n)trisQ, in which n represents alkyl chain carbon number) were characterized by equilibrium and dynamic surface tension, rheology, small-angle neutron scattering (SANS), and cryogenic transmission electron microscopy (cryo-TEM) techniques. 3C(n)trisQ showed critical micelle concentrations (CMC) 1 order of magnitude lower than that of the corresponding gemini surfactants with an ethylene spacer and the corresponding monomeric surfactants. The logarithm of the CMC decreased linearly with increasing hydrocarbon chain length for 3C(n)trisQ The slope of the line, which is well-known as Klevens equation, was larger than those of the monomeric and gemini surfactants; however, considering the total carbon number in the chains, the slope was shallower than the monomeric and was close to the gemini. Through the results such as surface tensions at the CMC (32-34 mN m(-1)) and the parameters of standard free energy, CMC/C-20 and pC(20), it was found that 3C(n)trisQ could adsorb densely at the air/water interface despite the strong electrostatic repulsion between multiple quaternary ammonium headgroups. Moreover, dynamic surface tension measurements showed that the kinetics of adsorption for 3C(n)trisQ to the air/water interface was slow because of their bulky structures. Furthermore, the results of rheology, SANS, and cryo-TEM determined that 3C(n)trisQ with n = 10 and 12 formed ellipsoidal micelles at low concentrations in solution and the structures transformed to threadlike micelles with very few branches for n = 12 as the concentration increased, but for n = 14 threadlike micelles formed at relatively low concentrations., 2012年06月, 28, 25, 9322, 9331, 研究論文（学術雑誌）, 10.1021/la301220y

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Supra-long chain surfactants with double or triple quaternary ammonium headgroups, Tomokazu Yoshimura; Nagisa Chiba; Keisuke Matsuoka, Novel supra-long chain surfactants with double or triple quaternary ammonium salts (C-n-2Am, C-n-3Am, in which n represents a hydrocarbon chain length of 18, 20, and 22) were synthesized, and electrical conductivity and surface tension were used to characterize their properties depending on both the hydrocarbon chain length and number of hydrophilic groups. The Krafft temperatures decreased remarkably with an increase in the quaternary ammonium headgroups, resulting in a high solubility in water. The critical micelle concentration (cmc) increased with an increase in the number of quaternary ammonium moieties in the hydrophilic group, and the difference in the cmc was smaller for C-n-2Am and C-n-3Am than for C-n-2Am and C-n-Am of alkyltrimethylammonium bromide. The surface tension at the cmc was approximately 45 and 48 mN m(-1) for C-n-2Am and C-n-3Am with n = 18-22, respectively. This indicated that the supra-long chain surfactants could not efficiently adsorb at the air/water interface and orient by themselves, as is known for conventional surfactants. (C) 2012 Elsevier Inc. All rights reserved., 2012年05月, 374, 1, 157, 163, 研究論文（学術雑誌）, 10.1016/j.jcis.2012.01.033

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Zwitterionic heterogemini surfactants containing ammonium and carboxylate headgroups 2: Aggregation behavior studied by SANS, DLS, and cryo-TEM, Kanae Nyuta; Tomokazu Yoshimura; Koji Tsuchiya; Hideki Sakai; Masahiko Abe; Hiroki Iwase, The aggregation behavior in aqueous solution of zwitterionic heterogemini surfactants, N,N-dimethyl-N-[2-(N'-alkyl-N'-beta-carboxypropanoylamino)ethyl]-1-alkylammonium bromides (2C(n)AmCa, in which n represents hydrocarbon chain lengths of 8, 10, 12, and 14), with nonidentical headgroups containing ammonium and carboxylate was investigated through small-angle neutron scattering (SANS), dynamic light scattering (DLS), and cryogenic transmission electron microscopy (cryo-TEM) techniques. We found that the aggregation behavior of 2C(n)AmCa strongly depended on the hydrocarbon chain length and the surfactant concentration. 2C(8)AmCa forms spherical micelles with radius of approximately 2 nm in solution. 2C(10)AmCa forms rod-like micelles at low concentration in the solution, and the structure changes to vesicles with increasing concentration. The membrane thickness of the vesicle is independent of the surfactant concentration. Aggregation shape transitions were also observed for 2C(12)AmCa. In addition, it appears that the vesicles of 2C(12)AmCa coexist with the rod-like micelles at a wide range of surfactant concentrations. Interestingly, 2C(14)AmCa forms vesicles with averaged membrane thickness of 2.32 nm in solution, even at the extremely low concentration of 10 times the cmc. Thus, it was concluded that 2C(n)AmCa exhibits unique aggregation behavior, such as the formation of spherical micelle -> rod-like micelle -> rod-like micelle + vesicle (coexistence) -> vesicle with increasing hydrocarbon chain length and surfactant concentration. We also found that the membrane structure is an interdigitated bilayer when the vesicles are formed. This formation of interdigitated structures is related to the origins of the effective properties of 2C(n)AmCa in solution. (C) 2011 Elsevier Inc. All rights reserved., 2012年03月, 370, 1, 80, 85, 研究論文（学術雑誌）, 10.1016/j.jcis.2011.12.027

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Effect of double quaternary ammonium groups on micelle formation of partially fluorinated surfactant, Keisuke Matsuoka; Nagisa Chiba; Tomokazu Yoshimura; Emi Takeuchi, To investigate the effect of divalency on the micelle properties, we synthesized divalent cationic surfactants composed of fluorocarbons and double quaternary ammonium groups N,N-dimethyl-N-[2-(N'-trimethylammonium)ethyl]-1-(3-perfluoroalkyl-2-hydroxypropyl) ammonium bromide [C(n)(F)C(3)-2Am; where n (=8 or 10) represents the number of carbon atoms in the fluorocarbon chain]. The double quaternary ammonium groups are continuously combined by the ethylene spacer in the surfactant head group, which clearly distinguishes the molecular design of the surfactant from those of the other typical divalent surfactants, bolaform and gemini types. The presence of the divalent head group results in an advantageous increase in their solubility [i.e., rise in the critical micelle concentration (cmc)]; however, the extra electrostatic repulsion between divalent cations decreases the surface activity in comparison with monovalent homologous fluorinated surfactants. The cmc, surface tension at cmc, and area occupied by a surfactant molecule in aqueous solution at 298.2 K are 4.32 mM, 30.6 mN m(-1), and 0.648 nm(2) molecule(-1), respectively, for C(8)(F)C(3)-2Am, and 1.51 mM, 30.4 mN m(-1), and 0.817 nm(2) molecule(-1), respectively, for C(10)(F)C(3)-2Am. The micellar size and shape were investigated by dynamic light scattering and freeze-fracture transmission electron microscopy (TEM). The TEM micrographs show that C(n)(F)C(3)-2Am (n = 8 and 10) mainly forms ellipsoidal micelles approximately 10-100 nm in size for n = 8 and approximately 10-20 nm in size for n = 10. The degree of counterion binding to micelle was determined by selective electrode potential measurements, and the results of 0.7-0.8 agree with the average values for conventional monovalent ionic surfactants. (C) 2011 Elsevier Inc. All rights reserved., 2011年04月, 356, 2, 624, 629, 研究論文（学術雑誌）, 10.1016/j.jcis.2011.01.030

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• 査読あり, 日本語, 色材協会誌, ヘテロジェミニ型界面活性剤の界面物性と会合挙動（特集・総説）, 吉村倫一, 2009年12月, 82, 12, 568-575
• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Surface properties and aggregate morphology of partially fluorinated carboxylate-type anionic gemini surfactants, Tomokazu Yoshimura; Miri Bong; Keisuke Matsuoka; Chikako Honda; Kazutoyo Endo, Three anionic homologues of a novel partially fluorinated carboxylate-type anionic gemini surfactant, N, N'-di(3-perfluoroalkyl-2-hydroxypropyl)-N, N'-diacetic acid ethylenediamine (2C(n)(F) edda, where n represents the number of carbon atoms in the fluorocarbon chain (4, 6, and 8)) were synthesized. In these present gemini surfactants, the relatively small carboxylic acid moieties form hydrophilic head groups. The surface properties or structures of the aggregates of these surfactants are strongly influenced by the non-flexible fluorocarbons and small head groups; this is because these surfactants have a closely packed molecular structure. The equilibrium surface tension properties of these surfactants were measured at 298.2 K for various fluorocarbon chain lengths. The plot of the logarithm of the critical micelle concentration (cmc) against the fluorocarbon chain lengths for 2C(n)(F) edda (n = 4, 6, and 8) showed a minimum for n = 6. Furthermore, the lowest surface tension of 2C(6)(F) edda at the cmc was 16.4 mN m (1). Such unique behavior has not been observed even in the other fluorinated surfactants. Changes in the shapes and sizes of these surfactant aggregate with concentration were investigated by dynamic light scattering and transmission electron microscopy (TEM). The TEM micrographs showed that in an aqueous alkali solution, 2C(n)(F) edda mainly formed aggregates with stringlike (n = 4), cagelike (n = 6), and distorted bilayer structures (n = 8). The morphological changes in the aggregates were affected by the molecular structure composed of nonflexible fluorocarbon chains and flexible hydrocarbon chains. (C) 2009 Elsevier Inc. All rights reserved., 2009年11月, 339, 1, 230, 235, 研究論文（学術雑誌）, 10.1016/j.jcis.2009.07.054

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• 査読あり, 英語, COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, Fluorocarbon-hydrocarbon gemini surfactant mixtures in aqueous solution, Kenichi Sakai; Megumi Kaji; Yuichiro Takamatsu; Koji Tsuchiya; Kanjiro Torigoe; Kazuyuki Tsubone; Tomokazu Yoshimura; Kunio Esumi; Hideki Sakai; Masahiko Abe, The aqueous solution properties of oppositely charged gemini-gemini surfactant mixtures have been studied with a combination of static surface tension, dynamic light scattering (DLS) and cryogenic transmission electron microscope (cryo-TEM) measurements. Two gemini surfactants were employed in this study: one is a partially fluorinated cationic gemini surfactant, 1,2-bis[dimethyl-(3-perfluorohexyl-2-hydroxypropyl)ammonium]ethane dibromide, and the other is a novel anionic gemini surfactant having hydrocarbon tail groups (N,N'-didodecyl-N,N'-dipropanesulfonylethylenediamine). Synergistic surfactant mixtures are frequently exploited to lower the mixed critical micelle concentration (cmc), however. such a decrease in the cmc is not observed in the current study. This suggests that limited mutual miscibility between the fluorocarbon and hydrocarbon tail groups plays a key role for the formation of the adsorbed layer, rather than attractive interactions such as electrostatic forces. On the other hand, spontaneous formation of vesicle-like molecular aggregates is suggested to occur as a result of their synergistic interaction in bulk solution. (C) 2008 Elsevier B.V. All rights reserved., 2009年02月, 333, 1-3, 26, 31, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2008.09.022

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• 査読あり, 英語, COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, Adsorption characteristics of sugar-based monomeric and gemini surfactants at the silica/aqueous solution interface, Kenichi Sakai; Mamoru Tamura; Shin Umezawa; Yuichiro Takamatsu; Kanjiro Torigoe; Tomokazu Yoshimura; Kunio Esumi; Hideki Sakai; Masahiko Abe, The adsorption behavior of sugar-based surfactants at the silica/aqueous solution interface has been characterized on the basis of the adsorption isotherm, potential and in situ atomic force microscopy (AFM) data. The surfactants used in the current work are monomeric Glu(n) (N-alkyl-N-methylgluconamide) and gemini Glu(n)-2-Glu(n) (N,N'-dialkyl-N,N'-digluconamide ethylenediamine), where n is the hydrocarbon chain length of 10 and 12. The adsorption isotherm reveals that, for all the surfactants, the adsorbed amount increases even above the critical micelle concentration (cmc) and an adsorption plateau region appears at the equilibrium concentration well above the cmc. The driving force for this adsorption is deemed to be a combination of the hydrogen bonding between the sugar moieties and the surface silanol groups and the intermolecular hydrophobic interaction of free monomers to the surfactants pre-adsorbed on silica. in the adsorption plateau region, the occupied area per molecule adsorbed on silica is calculated to be generally larger for the gemini surfactants than for the monomeric ones. This reflects the bulky structure of the headgroups of the sugar-based gemini surfactants and/or the relatively less favorable interaction of the headgroups with the silica surface. The combination of the soft-contact AFM and force curve data suggests that a structural transformation of the adsorbed layer occurs with an increase in the surfactant concentration, depending on the packing parameter of each surfactant. At the concentration above the cmc, the monomeric surfactants form either worm-like surface micelles or a patchy bilayer whereas the gemini surfactants only form a patchy bilayer. (C) 2008 Elsevier B.V. All rights reserved., 2008年10月, 328, 1-3, 100, 106, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2008.06.033

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• 査読あり, 英語, COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, Synthesis and aqueous solution properties of PAMAM dendron surfactants bearing a quaternary ammonium focal group and sugar terminal groups, Kanjiro Torigoe; Akihoko Tasaki; Tomokazu Yoshimura; Kenichi Sakai; Kunio Esurni; Yuichiro Takamatsu; Suraj Chandra Sharma; Hideki Sakai; Masahiko Abe, Poly(amidoamine) (PAMAM) dendron surfactants bearing a focal quaternary alkyldimethylammonium group and terminal sugar groups (C(m)qb-GnLac: m = 12, 18, 22; n = 0, 1) have been synthesized. Solution properties of these dendron surfactants were investigated by means of static surface tension, electric conductivity, fluorescence probing with pyrene, dynamic light scattering (DLS) and static light scattering (SLS). In the surface tension profiles all C(m)qb-GnLac systems indicate a clear break point corresponding to the critical micelle concentration (cmc). The cmc decreases with increasing length of alkyl chain, from 8.2 x 10(-3) (C-12) to 4.5 x 10(-6) mol dm(-3) (C-22) for G0Lac, from 1.0 X 10(-2) (C-12) to 3.7 x 10(-5) mol dm(-1) (C-22) for G I Lac systems. Unlike conventional cationic surfactants, the surface tension at cmc (gamma(cmc)) significantly increases with increasing alkyl chain length, associated with a slight increase in the molecular occupied area. Degree of counter ion (Br-) binding to the micelles is found to be very low due to an effective charge shielding by bulky non-ionic headgroups. In all C(m)qb-GnLac systems the micellar size decreases above a certain concentration. In the higher concentration regime, formation of micelles with a very small number of (at most a few) molecules is suggested from DLS data. (c) 2008 Elsevier B.V. All rights reserved., 2008年09月, 326, 3, 184, 190, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2008.05.036

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• 査読あり, 英語, JOURNAL OF OLEO SCIENCE, Adsorption of Cationic Monomeric and Gemini Surfactants on Montmorillonite and Adsolubilization of Vitamin E, Kenichi Sakai; Erimi Nakajima; Yuichiro Takamatsu; Suraj C. Sharma; Kanjiro Torigoe; Tomokazu Yoshimura; Kunio Esumi; Hideki Sakai; Masahiko Abe, Adsorption of a cationic gemini surfactant (1,2-bis(dodecyidimethylammonio) ethane dibromide, 12-2-12) and the corresponding monomeric surfactant (dodecyltrimethylammonium bromide, DTAB) on montmorillonite has been characterized with a combination of adsorption isotherm, interlayer spacing and FT-IR spectroscopic data. Adsolubilization of vitamin E into the adsorbed surfactant layers has also been studied. The adsorption isotherm data reveal that the adsorption of the two surfactants is driven by the two factors: one is the cation exchange that occurs on the interlayer basal planes and the other is the hydrophobic interaction between hydrocarbon chains of the surfactants. Although the adsorbed amount measured in the saturation region (in mol g(-1)) is almost identical for the two surfactants, the conformation of the intercalated surfactant molecules differs significantly from each other. The adsorption of DTAB results in a lateral bilayer arrangement in the limited interlayer space, whereas 12-2-12 gives a normal bilayer arrangement in the expanded interlayer space. Adsolubilization of vitamin E takes place into the adsorbed surfactant layers, and interestingly, all the vitamin E molecules added in the montmorillonite suspensions are hybridized at lower surfactant concentrations due to the great specific surface area of the clay material. Since the maximum adsolubilization amount is usually obtained just below the critical micelle concentration, the gemini surfactant is deemed to be more efficient than the corresponding monomeric one to achieve the great adsolubilization amount., 2008年08月, 57, 8, 423, 429, 研究論文（学術雑誌）, 10.5650/jos.57.423

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• 査読あり, 英語, LANGMUIR, Nanocage aggregates composed of bilayer sheets, Keisuke Matsuoka; Tomokazu Yoshimura; Miri Bong; Chikako Honda; Kazutoyo Endo, A partially fluorinated carboxylate-type anionic gemini surfactant, N,N'-di(3-perfluorohexyl-2-hydroxypropyl)-N,N'-diacetic acid-ethylenediamine (2C(6)(F)edda), formed aggregates with a cagelike structure in an aqueous alkali solution. These aggregates were composed of several bilayer sheets. The TEM micrograph showed that the bilayer sheets were produced from a condensed self-assembly core. The leaflike bilayer sheets-can form folds and link to each other at their edges. The typical size of the spherical cage ranged from ca. 200 to 1500 nm., 2008年06月, 24, 11, 5676, 5678, 研究論文（学術雑誌）, 10.1021/la800618v

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Adsorption and micellization behavior of novel gluconamide-type gemini surfactants, Kenichi Sakai; Shin Umezawa; Mamoru Tamura; Yuichiro Takamatsu; Koji Tsuchiya; Kanjiro Torigoe; Takahiro Ohkubo; Tomokazu Yoshimura; Kunio Esumi; Hideki Sakai; Masahiko Abe, The adsorption and micellization behavior of novel sugar-based gemini surfactants (N,N'-dialkyl-N,N'-digluconamide ethylenediamine, Glu(n)-2-Glu(n), where n is the hydrocarbon chain length of 8, 10 and 12) has been studied on the basis of static/dynamic surface tension, fluorescence, dynamic light scattering (DLS) and cryogenic transmission electron microscope (cryo-TEM) data. The static surface tension of the aqueous Glu(n)-2-Glu(n) solutions measured at the critical micelle concentration (cmc) is observed to be significantly lower than that of the corresponding monomeric surfactants. This suggests that the gemini surfactants, newly synthesized in the current study, are able to form a closely packed monolayer film at the air/aqueous solution interface. The greater ability in the molecular association is supported by the remarkably (approximately 100-200 times) lower cmc of the gemini surfactants compared with the corresponding monomeric ones. With a combination of the fluorescence and DLS data, a structural transformation of the Glu(n)-2-Glu(n) micelles is suggested to occur with an increase in the concentration. The cryo-TEM measurements clearly confirm the formation of worm-like micelles of Glu(12)-2-Glu(12) at the concentration well above the cmc. (C) 2007 Elsevier Inc. All rights reserved., 2008年02月, 318, 2, 440, 448, 研究論文（学術雑誌）, 10.1016/j.jcis.2007.10.039

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• 査読あり, 英語, 色材協會誌, Japan Society of Colour Material, Interaction Forces between BSA Adsorbed Layer on Amino-Thiolated Gold Surfaces, 吉村倫一, 2-アミノエタンチオールで修飾した金表面上に形成された牛血清アルブミン (BSA) の吸着層間の相互作用力の直接測定を, 原子間力顕微鏡 (AFM) のコロイドプローブ法を用いて行った。金板は, BSA溶液中で金表面の2-アミノエタンチオールの自己組織化によって調製した。BSAが存在しないとき, 金表面上での第一級アミンのプロトネーションにより, 電気二重層間の相互作用が見られた。同様の電気二重層間の反発が, BSAの存在下, 調べたBSAの全濃度で認められた。これらの斥力はBSAの濃度に依存し, 濃度増加にともない増大した。このことは, 27 MHz水晶発振子マイクロバランス (QCM) により, アミノエタンチオールで修飾した金表面におけるBSAの吸着量と関連付けることができた。, 2008年01月, 81, 1, 2-9, 9, 10.4011/shikizai.81.2

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• 査読あり, 英語, LANGMUIR, Molecular aggregates of partially fluorinated quaternary ammonium salt gemini surfactants, Keisuke Matsuoka; Tomokazu Yoshimura; Takashi Shikimoto; Juri Hamada; Mika Yamawaki; Chikako Honda; Kazutoyo Endo, The size and shape of novel partially fluorinated gemini surfactant 1,2-bis[dimethyl-(3-perfluoroalkyl-2F hydroxypropyl) ammonium] ethane bromide ((CnC3)-C-F-2-C3CnF, where n = 4, 6, and 8) were investigated in aqueous solution by means of light scattering and transmission electron microscopy (TEM). The sizes of these molecular aggregates changed with increasing carbon number of the alkyl chain and concentration. For example, the apparent hydrodynamic radius by dynamic light scattering was 18 nm at a concentration of cmc x 5 for n = 4, 115 urn at the cmc x 15 for it = 6, and 62 nm at the cmc x 30 for it = 8, at 298.2 K. The shapes of C-n(F) C-3-2-C3 C-n(F) aggregates drastically changed with the alkyl chain length; the aggregates were mainly in the form of large or irregular small auureaates (n = 4), string-like aggregates (n = 6), and vesicles (n = 8). The bromide-ion activity was measured using a bromide-ion-selective electrode to determine the degree of counterion binding to the aggregates. The degree of counterion binding to aggregate was very small compared with that in the typical hydrogenated gemini surfactants. These results indicated that the small curvature of large aggregates was not influenced by an electrostatic repulsion between the cationic head groups in the case of the bulky molecular volume of fluorinated gemini surfactants., 2007年10月, 23, 22, 10990, 10994, 研究論文（学術雑誌）, 10.1021/la701525c

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Adsorption and aggregation properties of amino acid-based N-alkyl cysteine monomeric and N,N '-dialkyl cystine gemini surfactants, Tomokazu Yoshimura; Ayako Sakato; Koji Tsuchiya; Takahiro Ohkubo; Hideki Sakai; Masahiko Abe; Kunio Esumi, An amino acid-based gemini surfactant derived from cystine (2C(n)Cys, where n represents the hydrocarbon chain lengths of 8, 10, and 12) was synthesized by reacting cystine with n-alkyl bromide, and its adsorption and aggregation properties were characterized by measurements of equilibrium and dynamic surface tension and dynamic light scattering. The properties of 2CnCys were compared with those of an amino acid-based monomeric surfactant derived from cysteine (C(n)Cys). For n = 8 and 10, when compared to C(n)Cys, 2C(n)Cys exhibited excellent surface activities, such as a lower critical micelle concentration (cmc), greater efficiency in lowering the surface tension of water, and smaller area occupied per molecule. Adsorption rate at air/water interface decreased with an increase in hydrocarbon chain length, chain number, and concentration of respective compounds. Further, the kinetics were discussed using the monomer diffusion coefficient obtained from short and long time scales in dynamic surface tension plots. In addition, the aggregation properties of 2C(n)Cys for n = 8 and 10 differed from those in the case of n = 12. In other words, relatively larger micelles with diameters of approximately 7 nm were formed by 2C(n)Cys for n = 8 and 10 in comparison to those formed by C(n)Cys (2-3 nm). On the other hand, for a 0.832 mmol dm(-3) 2C(12)Cys solution, the aggregation structure investigated by cryogenic transmission electron microscopy (cryo-TEM) and small-angle neutron scattering (SANS) revealed the coexistence of small unilamellar vesicles and small rods. (c) 2006 Elsevier Inc. All rights reserved., 2007年04月, 308, 2, 466, 473, 研究論文（学術雑誌）, 10.1016/j.jcis.2006.11.038

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Adsolubilization of 2-naphthol into adsorbed layers of triblock PEO-PPO-PEO copolymers on hydrophobic silica particles, Daisuke Tsurumi; Kenichi Sakai; Tomokazu Yoshimura; Kunio Esumi, Adsolubilization of 2-naphthol into an adsorbed layer of triblock poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEOPPO-PEO, Pluronics) copolymers on hydrophobically modified silica particles has been investigated. Four kinds of Pluronics (P103, P105, P123, and F108) were employed in order to understand the effect of the hydrophobicity of the surfactants on the adsolubilization. The amount of the Pluronics adsorbed of the maximum/saturation adsorption level was increased with a decrease in the HLB value, suggesting that the more hydrophobic Pluronics (P103 and P123) adsorb preferentially onto the hydrophobic silica surface over the more hydrophilic Pluronics (P105 and F108). The greater adsorbed amount of the more hydrophobic surfactants resulted in a greater amount of 2-naphthol adsolubilized into the adsorbed Pluronics layers. In the case of simultaneous addition of the Pluromes and 2-naphthol, the amount adsolubilized into the adsorbed P123 and P103 layers increased in their low-surfactant-concentration regime, reached a maximum, and then decreased with a further increase in the Pluronics concentration. On the other hand, for both the P105 and F108 copolymers, a decrease in the adsolubilized amount was not observed over the whole range of copolymer concentration investigated. This difference is attributed to a difference in the hydrophobicity of the micellar aggregates in solution and of the adsorbed layers on the hydrophobic surface. When 2-naphthol was added after replacement of the Pluronics supernatant by a surfactant-free solution, the final decrease in the adsolubilization was insignificant for all the Pluronics. Indeed, the maximum amount of adsolubilization was comparable to the corresponding amount obtained in the case of simultaneous addition. (c) 2006 Elsevier Inc. All rights reserved., 2006年10月, 302, 1, 82, 86, 研究論文（学術雑誌）, 10.1016/j.jcis.2006.06.012

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Scavenging DPPH radicals catalyzed by binary noble metal-dendrimer nanocomposites, Takeshi Endo; Takae Fukunaga; Tomokazu Yoshimura; Kunio Esumi, Catalytic activity of gold-platinum, gold-palladium, and platinum-palladium dendrimer nanocomposites for scavenging 1,1-diphenyl-2picrylhydrazyl (DPPH) radicals was investigated. The gold-platinum and gold-palladium dendrimer nanocomposites were prepared via simultaneous reduction by sodium borohydride in the presence of poly(amidoamine) (PAMAM) dendrimers with amine or carboxyl terminal groups. The particles were not mixtures of monometallic particles but alloyed bimetallic particles. Bimetallic particles exhibited higher catalytic activity than monometallic ones. (c) 2006 Elsevier Inc. All rights reserved., 2006年10月, 302, 2, 516, 521, 研究論文（学術雑誌）, 10.1016/j.jcis.2006.06.053

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• 査読あり, 英語, LANGMUIR, Adsorption and aggregation properties of heterogemini surfactants containing a quaternary ammonium salt and a sugar moiety, Kanae Nyuta; Tomokazu Yoshimura; Koji Tsuchiya; Takahiro Ohkubo; Hideki Sakai; Masahiko Abe; Kunio Esumi, A novel heterogemini surfactant comprising two hydrocarbon chains and two different hydrophilic groups such as a quaternary ammonium cation and gluconamide nonion N,N-dimethyl-N-[2-(N'-alkyl-N'-gluconamide)ethyl]-1-alkylammonium bromides (2C(n)AmGlu, where n represents hydrocarbon chain lengths of 8, 10, 12, and 14) was synthesized by reacting N,N-dimethylethylenediamine with alkyl bromide, followed by a reaction with 1,5-D(+)gluconolactone. The adsorption properties of 2C(n)AmGlu were characterized by surface tension measurements made using the Wilhelmy plate method, and their aggregation properties were investigated by dynamic light scattering and cryogenic transmission electron microscopy techniques. The relationship between the hydrocarbon chain length and the logarithm of the critical micelle concentration (cmc) for 2C(n)AmGlu exhibited a linear decrease when the chain length was increased up to 12 and then a departure from linearity at n = 14. The surface tension reached 24-26 mN m(-1) at each cmc, indicating high efficiency in lowering the surface tension of water. Furthermore, it was found that the structure of the aggregate formed for 2CnAmGlu in solution was influenced by the hydrocarbon chain length; that is, for n = 10 and 12, micelles with a hydrodynamic radius of 2-5 nm were formed, whereas vesicles were also observed for n = 14., 2006年10月, 22, 22, 9187, 9191, 研究論文（学術雑誌）, 10.1021/la061688h

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Surface tension and micellization properties of heterogemini surfactants containing quaternary ammonium salt and sulfobetaine moiety, Kanae Nyuta; Tomokazu Yoshimura; Kunio Esumi, A novel gemini surfactant with two hydrocarbon chains and two different hydrophilic parts containing a quaternary ammonium salt and a sulfobetaine moiety, N,N-dimethyl-N-{2-[N'-methyl-N'-(3-sulfopropyl)-alkylammonium]ethyl}-1-alkylammonium bromides (2C(n)AmSb, where n represents hydrocarbon chain lengths of 8, 10, 12, and 14), was synthesized by reacting N,N,N'-trimethylethylenediamine with n-alkyl bromide, followed by reacting with 1,3-propane sultone. The adsorption and aggregation properties of 2C(n)AmSb in the absence and presence of NaCl were characterized by the measurement of surface tension, steady-state fluorescence, and dynamic light scattering. The critical micelle concentration (cmc) and surface tension at the emc of 2C(n)AmSb were compared with those for the corresponding monomeric surfactants, their mixtures, and gemini surfactants. The poor solubility in water shown by 2C(n)AmSb was improved by the addition of NaCl. The cmc of 2C(n)AmSb in the presence of NaCl is lower than that in the absence of NaCl, and the surface tension is almost identical for both systems. The radius of the aggregates formed by 2C(n)AmSb in a solution containing NaCl is found to be 0.70 +/- 0.3, 2.5 +/- 0.7, 5.6 +/- 1.4, and 10.7 +/- 2.4 nm for n = 8, 10, 12, and 14, respectively. The particle size increases with an increase in hydrocarbon chain length; in particular, relatively large aggregates are formed for n = 12 and 14. (c) 2006 Elsevier Inc. All rights reserved., 2006年09月, 301, 1, 267, 273, 研究論文（学術雑誌）, 10.1016/j.jcis.2006.04.075

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Interaction forces between poly (amidoamine) (PAMAM) dendrimers adsorbed on gold surfaces, D Hiraiwa; T Yoshimura; K Esumi, Interaction forces between two gold surfaces with adsorbed poly(amidoamine) (PAMAM) dendrimers (generations G3.0 and G5.0) have been investigated using colloidal probe atomic force microscopy (AFM). In the absence of dendrimers or at their low concentrations, an attractive force derived from the van der Waals interaction was observed. On the other hand, this attractive interaction changed to repulsion with increasing dendrimer concentration. The origin of the repulsion can be attributed to either an electric double layer interaction or a steric effect of the adsorbed dendrimers, depending on the concentration of dendrimer. The steric hindrance was also influenced by the generation of the dendrimer; the force-detectable distance in the presence of PAMAM G5.0 dendrimer was slightly longer than that in the presence of G3.0 dendrimer. In order to estimate the occupied area of each dendrimer adsorbed on gold, quartz crystal microbalance (QCM) measurement was also carried out. (c) 2006 Elsevier Inc. All rights reserved., 2006年06月, 298, 2, 982, 986, 研究論文（学術雑誌）, 10.1016/j.jcis.2005.12.060

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• 査読あり, 英語, COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, Azeotropic mixing Of C(16)peLac with different surfactants of monomeric and dimeric nature under the effect of temperature, MS Bakshi; G Kaur; T Yoshimura; K Esumi, The steady state fluorescence measurements have been performed for the binary mixtures of N-hexadecyl-N'-lactobionylethylenediamine (C(16)peLac) with a variety of surfactants such as 3-(N,N-dimethylhexadecylammonio) propane sulphonate (HPS), dodecylhexadecyldimethyl ammonium bromide (12-0-16), trimethylene-1,3-bis(dodecyldimethylammonium bromide) (12-3-12), and hexamethylene-1,6bis(dodecyldimethylammonium bromide) (12-6-12) over the whole mixing range in the temperature range of 15-45 degrees C. From the variation of I-1/I-3 intensity ratio of pyrene fluorescence, the critical micelle concentration (cmc) of single and mixed surfactants has been determined. The nature of the mixed micelles has been evaluated with the help of regular solution theory. The micellar parameters such as micelle mole fraction (X-1), and regular solution interaction parameter (beta), have been determined for all the binary mixtures. It has been observed that the mixed micelles of C(16)peLac + 12-0-16/HPS are formed due to synergistic interactions while unfavorable interactions have been found during the mixed micellization of C(16)peLac + 12-3-16/12-6-12 mixtures. The former behavior came from the reduction in the polar head group repulsions of 12-0-16 and HPS upon the intercalation of C(16)peLac. On the other hand, large spacer groups in bulky dimeric head groups as in case of 12-3-12 and 12-6-12 results in unfavorable interactions with C(16)peLac. (c) 2006 Elsevier B.V. All rights reserved., 2006年06月, 281, 1-3, 163, 170, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2006.02.058

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• 査読あり, 英語, LANGMUIR, Equilibrium and dynamic surface tension properties of partially fluorinated quaternary ammonium salt gemini surfactants, T Yoshimura; A Ohno; K Esumi, The equilibrium and dynamic surface tension properties of a partially fluorinated quaternary ammonium salt gemini surfactant 1,2-bis[dimethyl-(3-perfluoroalkyl-2-hydroxypropyl)ammonium]ethane bromide ((CnC3)-C-F-2-C3CnF, where n represents fluorocarbon chain lengths of 4, 6, and 8) were investigated, and the effects of the fluorocarbon chain length and the number of chains on them were discussed. The plot of the logarithm of the critical micelle concentration (cmc) against the fluorocarbon chain length for (CnC3)-C-F-2-C-3 C-n(F) showed a linear decrease with an increase in chain length. On the basis of the slope of this plot, it was found that the variation in cmc with respect to the chain length is large for fluorinated gemini surfactants. The surface tension at the cmc decreased significantly; this surface tension value is lower than that of conventional fluorinated monomeric surfactants. In particular, the lowest value was 13.7 mN m(-1) for n = 8. Furthermore, it was confirmed that the kinetics of adsorption at the interface decrease with an increase in the fluorocarbon chain length and the concentration., 2006年05月, 22, 10, 4643, 4648, 研究論文（学術雑誌）, 10.1021/la0534266

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Adsolubilization of 2-naphthol into adsorbed layer of PEO-PPO-PEO triblock copolymers on hydrophilic silica, D Tsurumi; T Yoshimura; K Esumi, Adsolubilization of 2-naphthol into an adsorbent layer of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) triblock copolymers (Pluronics) on hydrophilic silica has been investigated. Four kinds of Pluronics (P103, P105, P123, and F108) were used in order to understand the effect of the hydrophobicity of surfactant on the adsolubilization. The order of the adsorption in the saturation level was found to be P123 approximate to P103 > P105 >> F108, meaning that Pluronics with higher hydrophobicity can adsorb perferentially to the silica surface. Indeed, this order was parallel to the order of the adsolubilization amount of 2-naphthol. In the case of co-addition of the Pluronics and 2-naphthol, the adsolubilization amount increased gradually at lower surfactant concentration regions, reached a maximum, and then decreased with increasing concentration of the Pluronics. The maximum amount appeared at critical polymolecular micelle concentration of each Pluronics. On the other hand, the final decrement was not observed when 2-naphthol was added after replacement of the Pluronics supernatant by the Pluronics free solution. These results suggest that adsolubilization behavior is influenced by the existence of the polymolecular micellar aggregates in the solution phase. (c) 2005 Elsevier Inc. All rights reserved., 2006年05月, 297, 2, 465, 469, 研究論文（学術雑誌）, 10.1016/j.jcis.2005.11.027

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• 査読あり, 英語, COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, Spectroscopic investigation on the hydrophobicity in the mixtures of nonionic plus twin tail alkylammonium bromide surfactants, MS Bakshi; K Singh; G Kaur; T Yoshimura; K Esumi, The mixed micelle study of C10E8, C12E4, and C14E8 nonionic surfactants with 12-0-8, 12-0-10, 12-0-12, and 12-0-16 twin tail alkylammonium bromides has been carried out with the help of pyrene fluorescence, dynamic light scatterings (DLS), and electron spin resonance (ESR) measurements. The pyrene fluorescence allowed us to determine the mixed cmc and aggregation number (N-agg), while the size of the mixed aggregates, and rotation correlation time (tau(c),) of the spin probe have been evaluated from DLS and ESR, respectively. Application of the regular solution theory showed that the mixed micelle formation in the mixtures of C10E8/C12E4 + cationic surfactants occurred due to the synergistic interactions, and the regular solution theory interaction parameter, beta, became more negative with an increase in the hydrophobicity of the cationic component. A variation in the micelle mole fraction suggested that the mixed micelles are mainly rich in the nonionic component. An increase in the hydrophobicity of the nonionic surfactant from C10E8 to C14E8 induced antagonistic mixing in the mixtures of C14E8 with cationic surfactants of longer hydrophobic tail. This was attributed to the mutual incompatibility among the longer hydrophobic tails of the unlike components. The DLS and ESR measurements fully supported the above results, where the size of the aggregates increases with the increase in hydrophobicity. (c) 2005 Elsevier B.V. All fights reserved., 2006年04月, 278, 1-3, 129, 139, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2005.12.009

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• 査読あり, 英語, COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, Interaction of cationic gold nanoparticles and carboxylate-terminated poly(amidoamine) dendrimers, A Okugaichi; K Torigoe; T Yoshimura; K Esumi, Interaction between cationic gold nanoparticles ligated with 3-mercaptopropyltrimethylammonium chloride (MPTAC) and anionic poly(amidoamine) (PAMAM) dendrimers with carboxylate, terminals (Generation 3.5 and 5.5-COONa) has been investigated in aqueous solution and on carbon film by UV-vis, TEM, DLS and zeta potential measurements. In the absence of PAMAM dendrimers, the MPTAC-Au nanoparticles in water exhibited a surface plasmon resonance (SPR) band at 520 nm. The gold particles of 4.2 nm in mean diameter were homogeneously dispersed on the carbon grids. Addition of PAMAM brought about an increase in the absorbance and redshift of the SPR band, which was attributed to aggregation of the gold nanoparticles by adsorption of the dendrimer to the MPTAC ligand layers owing to electrostatic attraction. In particular, chainlike aggregates were formed at low concentrations of the dendrimer (r = [PAMAM]/[MPTAC] <= 1). While a further increase in the dendrimer concentration (r = 2) led to a remarkable decrease in the size of aggregates, and; m,, of the SPR band returned to approximately the same wavelength as that for r = 0.5. (c) 2005 Elsevier B.V. All rights reserved., 2006年02月, 273, 1-3, 154, 160, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2005.08.028

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• 査読あり, 英語, JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY, Preparation and catalytic activity of Au-Pd, Au-Pt, and Pt-Pd binary metal dendrimer nanocomposites, T Endo; T Kuno; T Yoshimura; K Esumi, Catalytic activity of Au-Pt, Au-Pd, and Pt-Pd dendrimer nanocomposites for reduction of p-nitrophenol was investigated in water. The bimetallic dendrimer nanocomposites were prepared by simultaneous reduction with sodium borohydride in the presence of poly(amidoamine) (PAMAM) dendrimers with amine and carboxyl terminal groups. Average diameters of the obtained particles were 2-4 nm by transmission electron microscopy. From UV-vis spectroscopy, it was found that the particles were not mixtures of monometallic particles but binary ones. X-ray photoelectron spectroscopy showed that formation of binary composite particles prevents palladium atoms from oxidation. The Au-Pd and Pt-Pd binary particles exhibited higher catalytic activity than monometallic ones. On the other hand, catalytic activity of Au-Pt binary particle was comparable to that of platinum nanoparticles., 2005年11月, 5, 11, 1875, 1882, 研究論文（学術雑誌）, 10.1166/jnn.2005.438

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• 査読あり, 英語, LANGMUIR, Sugar-based gemini surfactants with peptide bonds-synthesis, adsorption, micellization, and biodegradability, T Yoshimura; K Ishihara; K Esumi, The sugar-based gemini surfactant with peptide bonds, N,N-bisalkyl-NN'-bis[2-(lactobionylamide)-ethyl]hexanediamide (2C(n)peLac, in which n represents hydrocarbon chain lengths of 12 and 16), was synthesized by reacting adipoyl chloride with the corresponding monomeric surfactant N-alkyl-N'-lactobionylethylenediamine (C(n)peLac), which was obtained by reacting ethylenediamine with alkyl bromide and lactobionic acid. The adsorption and micellization properties of C(n)peLac and 2C(n)peLac were characterized by the measurement of their equilibrium and dynamic surface tension, steady-state fluorescence using pyrene as a probe, dynamic light scattering (DLS), and time-resolved fluorescence quenching (TRFQ), and their biodegradability was also investigated. The critical micelle concentration (cmc) decreases with an increase in the hydrocarbon chains from monomeric to gemini surfactants, whereas it increases with an increase in the chain length from 12 to 16 for both systems. The increases in both the hydrocarbon chain the h h ower e and the chain length of sugar-based surfactants reduce surface activities suc surface tension, the occupied area per molecule, and the adsorption rate at the air/water interface. The sugar-based surfactants CnPeLac and 2CnpeLac exhibit unique aggregation behavior in aqueous solution. The DLS results indicate that the apparent hydrodynamic diameter of CnpeLac micelles decreases sharply with increasing concentration, whereas that of 2C(n)peLac micelles decreases gradually. From the TRFQ measurement, it was observed that, as concentration increases, the aggregation numbers are almost constant for C(n)peLac, whereas they increase for 2C(n)peLac. These results imply that loosely packed micelles formed by sugar-based surfactants become tightly packed micelles as the concentration increases. Furthermore, it was found that 2C(n)peLac shows lower biodegradability than does C(n)peLac because it contains tertiary amines in the molecule., 2005年11月, 21, 23, 10409, 10415, 研究論文（学術雑誌）, 10.1021/la051614q

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• 査読あり, 英語, COLLOID AND POLYMER SCIENCE, Characterization of aliphatic and aromatic polyester hyperbranched dendrimers by AFM imaging, MS Bakshi; R Sood; G Kaur; K Sakai; T Yoshimura; K Esumi, The aggregates of aliphatic (AL-PE) and aromatic polyester (AR-PE) hyperbranched dendrimers were imaged by tapping mode atomic force microscopy (AFM). The second and third generations of AL-PE dendrimers were adsorbed on mica in large aggregates of 150- and 166-nm diameters with little heights (ca. 1-2 nm). The origin of such flattened aggregates is attributed to their favorable adsorption on mica in view of the presence of -OH surface groups. AR-PE did not show such flattened aggregates instead small aggregates of 63 nm were observed in an organized manner beaving a cavity in the center of each aggregate. The organized aggregates of AR-PE with smaller dimension than AL-PE are ascribed to less favorable adsorption of the latter on mica in view of its stronger hydrophobicity., 2005年10月, 284, 1, 74, 79, 研究論文（学術雑誌）, 10.1007/s00396-005-1322-5

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• 査読あり, 英語, 色材協會誌, 一般社団法人 色材協会, Antioxidant Activity of Noble Metal (Gold, Platinum)-Biopolymer Nanocomposites PartII, 吉村倫一, 白金-生体高分子ナノコンポジットをフコイダン, アルギン酸, ヒアルロン酸ナトリウムを用いて調製した。白金-フコイダンナノコンポジットでは平均粒径は3.1-2.6nmとなり, フコイダン濃度の減少とともに小さくなった。白金-ヒアルロン酸ナトリウムナノコンポジットでは平均粒径は3.4-3.8nmとなり, ヒアルロン酸ナトリウム濃度の減少とともに大きくなった。白金-アルギン酸では平均粒径は3.2-3.4nmとなり, 生体高分子の濃度の影響は小さかった。白金-生体高分子ナノコンポジットのヒドロキシルラジカルの消去活性は, 生体高分子の種類と濃度に依存した。消去活性は, アルギン酸>ヒアルロン酸ナトリウム>フコイダンの順に大きく, また, 生体高分子の濃度が減少すると大きくなることが明らかになった。さらに, 白金-生体高分子ナノコンポジットは金-生体高分子ナノコンポジットに比べて高い消去活性能を示した。とくに, 白金-アルギン酸ナノコンポジットは代表的な抗酸化物質であるアスコルビン酸の約110倍も大きな活性を示すことがわかった。, 2005年09月, 78, 9, 409-416, 416, 10.4011/shikizai1937.78.409

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• 査読あり, 英語, COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, Topographical and photophysical properties of poly(amidoamine) dendrimers with ionic surfactants, MS Bakshi; A Kaura; R Sood; G Kaur; T Yoshimura; K Torigoe; K Esumi, The atomic force microscopy (AFM) and transmission electron microscopy (TEM) have been performed on the poly(amidoamine) dendrimers of second generation (2G) and its fluoroderivative (2D) at room temperature. Both studies have demonstrated that 2G and 2D exist in large aggregates on solid surface. The presence of ionic surfactants facilitates their solubilization in micellar phase resulting in the aggregates of much smaller dimensions. The aqueous bulk properties of 2G and 2D both in the absence as well as in the presence of ionic surfactants (i.e. dodecyltrimethylammonium bromide (DTAB), dimethylene bis (dodecyldimethylammonium bromide) (12-2-12), and sodium dodecyl sulfate (SDS)) have been carried out with the help of pyrene fluorescence and turbidity (tau) measurements. From the variation of I-1/I-3 pyrene intensity and the T of these aqueous solutions, it has been found that both DTAB and 12-2-12 interact with the surface groups of 2G and 2D favorably in basic medium, while SDS has been found to interact with that in acidic medium. Apart from this, interactions of cationic surfactants have been found to be stronger with 2D in comparison to 2G, while reverse has been observed in the case of SDS. (c) 2005 Elsevier B.V. All rights reserved., 2005年09月, 266, 1-3, 181, 190, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2005.06.059

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Preparation of Au/TiO2 nanocomposites and their catalytic activity for DPPH radical scavenging reaction, R Isono; T Yoshimura; K Esumi, Au/TiO2 nanocomposites have been prepared by UV photolysis or chemical reduction of a Au(III) complex formed on a spherical or a rodlike TiO2 support, and their catalytic activity for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging reaction was investigated. The chemical reduction with dimethylamine borane (DMAB) provided smaller gold nanoparticles than those synthesized by UV photolysis. Type of the TiO2 also affected the size of gold particles; smaller gold particles were deposited on the spherical TiO2 support than on rodlike one. For the radical scavenging reaction, the Au/TiO2 nanocomposites prepared by chemical reduction exhibited a higher catalytic activity than those photochemically prepared, and rodlike TiO2 provided a higher activity than spherical one. The effects of preparation methods and type of TiO2 supports on the catalytic activity are discussed. (c) 2005 Elsevier Inc. All rights reserved., 2005年08月, 288, 1, 177, 183, 研究論文（学術雑誌）, 10.1016/j.jcis.2005.02.078

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• 査読あり, 英語, 色材協會誌, 一般社団法人 色材協会, Morphological Change of Calcium Carbonate Prepared in Aqueous Dendrimer Solutions, 吉村倫一, 塩化カルシウム, 尿素, およびカルボキシル末端基をもつポリアミドアミン (PAMAM) デンドリマー (世代 1.5, 3.5, 5.5) を含む水溶液を用いて, 炭酸カルシウム結晶を90℃で調製した。デンドリマー非存在下では, 針状のアラゴナイト型結晶が生成したが, デンドリマー存在下では, デンドリマーの濃度の増加とともに球状のバテライト型結晶へ形態が変化した。 もう1つの調製方法として, 塩化カルシウム, 尿素, 酵素ウレアーゼ, およびデンドリマーを含む溶液から, 炭酸カルシウム結晶を25℃で調製した。溶液の透過率や粉末 X 線回折結果から, デンドリマー非存在下ではカルサイト型結晶のみが生成するのに対し, デンドリマー存在下ではバテライト型結晶が生成し, 時間とともにカルサイト型結晶へ形態が変化することが明らかとなった。, 2005年06月, 78, 6, 254-259, 259, 10.4011/shikizai1937.78.254

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• 査読あり, 英語, Langmuir, Zwitterionic heterogemini surfactants containing ammonium and carboxylate headgroups. 1. Adsorption and micellization, Tomokazu Yoshimura; Kanae Nyuta; Kunio Esumi, Zwitterionic heterogemini surfactants with two hydrocarbon chains and two different hydrophilic groups, N,N-dimethy-N- [2-(N′-alkyl-N′-β- carboxypropanoylamino)ethyl]- 1-alkylammonium bromides (2CnAmCa, where n represents the hydrocarbon chain lengths of 8, 10, 12, and 14), were synthesized by N,N-dimethylethylenediamme with alkyl bromide, followed by reaction with succinic anhydride. One of the hydrophilic groups is a carboxylate anion, and the other is an ammonium cation. Their physicochemical properties were characterized by measuring equilibrium and dynamic surface tension, fluorescence intensity of pyrene, and light-scattering intensity. A relationship between a logarithm of critical micelle concentration (cmc) and hydrocarbon chain length showed a linear decrease upon increasing chain length and then a departure from linearity at n = 14. This is due to the existence of premicellar aggregations at concentrations below the cmc for n = 14. The surface tension of 2CnAmCa reached 27-30 mN m-1 at each cmc, indicating efficiencies typical of hydrocarbon chain surfactants. The adsorbing rate at the air/water interface became slow with an increase of the chain length. From the fluorescence intensity ratios of 373 and 384 nm using pyrene as a probe, for n = 8, 10, and 14, the pyrene was solubilized in surfactant micelles at around the cmc, whereas for n = 12 the pyrene was solubilized from a concentration of 10-fold the cmc. The scattering intensities by dynamic light scattering also increased from around these concentrations for each chain length, showing the formation of aggregates in solution. © 2005 American Chemical Society., 2005年03月29日, 21, 7, 2682, 2688, 研究論文（学術雑誌）, 10.1021/la047773b

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Synthesis and catalytic activity of gold-silver binary nanoparticles stabilized by PAMAM dendrimer, T Endo; T Yoshimura; K Esumi, Gold-silver binary nanoparticles, which feed atomic ratios of gold to silver were 3: 1, 1: 1, and 1:3, were prepared. These particles were stabilized by amine-terminated (generation (G) 3.0 and 5.0) and carboxyl-terminated (G 3.5 and 5.5) poly(amidoamine) (PAMAM) dendrimers in water. UV-vis spectra indicate that the particles are not mere physical mixtures of monometallic particles or core/shell type but alloy. According to transmission electron microscope (TEM) observation, the mean diameters of the particles were 7-10 nm for silver particles and 3-4 nm for both gold and alloy particles, respectively. Catalytic activities for reduction of p-nitrophenol were investigated by monitoring the absorbance at 400 nm during the reaction. They were proportional to the feed ratio of gold in the particles and showed a maximum at the ratio of Au:Ag = 3: 1. (c) 2005 Elsevier Inc. All rights reserved., 2005年06月, 286, 2, 602, 609, 研究論文（学術雑誌）, 10.1016/j.jcis.2005.01.057

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Preparation of gold-, gold/silver-dendrimer nanocomposites in the presence of benzoin in ethanol by UV irradiation, K Esumi; T Matsumoto; Y Seto; T Yoshimura, Gold- and gold/silver-dendrimer nanocomposites have been synthesized by UV irradiation of their salts dissolved in ethanol containing dendrimers. As dendrimers, poly(amidomaine) PAMAM dendrimers and poly(propyleneimine) PPI dendrimers of various generations were used, The photoreduction of their salts is greatly accelerated by using benzoin as a photoinitiator. The sizes of gold in the nanocomposites are affected by the concentration of benzoin as well as the concentration of dendrimers, but are hardly changed with the kind of dendrimers. For gold/silver-dendrimer nanocomposites, the absorption spectra of gold/silver nanoparticles in the nanocomposites are very similar to the theoretical spectra of gold/silver alloy nanoparticles, suggesting the formation of gold/silver alloy nanoparticles. From the comparison of TEM and DLS measurements, it is found that the metal-dendrimer nanocomposites consist of metal nanoparticles covering by dendrimer molecules. (c) 2004 Elsevier Inc. All rights reserved., 2005年04月, 284, 1, 199, 203, 研究論文（学術雑誌）, 10.1016/j.jcis.2004.09.020

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• 査読あり, 英語, 色材協會誌, 一般社団法人 色材協会, Antioxidant Activity of Noble Metal (Gold, Platinum)-Biopolymer Nanocomposites, 吉村倫一, 金-生体高分子ナノコンポジットをフコイダン, アルギン酸, ピアルロン酸ナトリウムを用いて調製した。金一フコイダンナノコンポジットでは平均粒径は3. 2-6. 8nmとなり, フコイダン濃度の減少とともに小さくなった。金一アルギン酸と金一ピアルロン酸ナトリウムナノコンポジットでは平均粒径は3. 4-5. 4nmとなり, 生体高分子の濃度の影響は小さかった。金一生体高分子ナノコンポジットのヒドロキシルラジカルの消去活性は, 生体高分子の種類と濃度に依存した。消去活性は, アルギン酸>ヒアルロン酸ナトリウム>フコイダンの順に大きいことがわかった。また, 生体高分子の濃度が減少すると大きくなることがわかった。とくに, 金一アルギン酸ナノコンポジットは代表的な抗酸化物質であるアスコルビン酸の約60倍も大きい活性を示した, 2005年03月, 78, 3, 112-121, 121, 10.4011/shikizai1937.78.112

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• 査読あり, 英語, COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, Characterization of quaternized poly (amidoamine) dendrimers of generation 1 with multiple octyl chains, T Yoshimura; S Abe; K Esumi, A quaternized dendrimer-type surfactant with 16 octyl chains and 16 ammonium groups (refer to C(8)qbGl) has been synthesized by the reaction of poly(amidoamine) dendrimer of generation I with glycidyldimethyloctylammonium bromide, and its physicochemical properties have been characterized by measuring surface tension, fluorescence spectroscopy of pyrene, specific conductivity, dynamic light-scattering (DLS) and electrophoretic light-scattering (ELS). The surface tension of C(8)qbGl decreases gradually with increasing concentration, and reaches two break points, probably indicating that the quaternized dendrimers adsorb and saturate at the air/water interface, and then interact strongly with them being at the interface. The concentrations at two break points coincide with those obtained by the electrical conductivity method. The fluorescence intensity ratio of the first to the third band in the emission spectrum of pyrene for C(8)qbGl continues to decrease slowly from 3-fold-concentration of first break point obtained by the surface tension method. In addition, the results of DLS and ELS show that C(8)qbGl forms large aggregates with positive-potentials in the solution, and these sizes become large with the concentration. One of the reasons for such a bulk behavior may be caused by the attractive interaction between multiple hydrocarbon chains of C(8)qbGl. (C) 2004 Elsevier B.V. All rights reserved., 2004年12月, 251, 1-3, 141, 144, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2004.09.031

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• 査読あり, 英語, 色材協會誌, 一般社団法人 色材協会, Comparison of Gold-PAMAM and Gold-PPI Dendrimer Nanocomposites for Antioxidant Action, 吉村倫一, 金-デンドリマーナノコンポジットをポリ (アミドアミン) (PAMAM) デンドリマー (世代3, 3.5, 5, 5.5) およびポリ (プロピレンイミン) (PPI) デンドリマー (世代3, 4) を用いて, HAuCl₄とホウ化水素ナトリウムの還元により調製した。金ナノ粒子の平均粒径は, デンドリマーの濃度ならびに世代に依存せず, PAMAMデンドリマーでは直径3.0～4.3nm, PPIデンドリマーでは直径2.1～2.3nmであった。H₂O₂/FeSO₄において, ヒドロキシラジカルの消去における金-デンドリマーナノコンポジットの触媒活性を, スピンートラッピング法を用いて検討した。金-PPIデンドリマーナノコンポジットの触媒活性は, 金-PAMAMデンドリマーナノコンポジットよりもわずかに低かった。さらに, 金-デンドリマーナノコンポジットは高い触媒活性を示し, 世代3.5のPAMAMデンドリマーを除いてデンドリマーの濃度ならびに世代にはほとんど影響を受けなかった。金と世代3.5のPAMAMデンドリマーナノコンポジットのもっとも高い活性はアスコルビン酸の85倍であった。, 2004年11月, 77, 11, 487-492, 492, 10.4011/shikizai1937.77.487

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Association behavior of poly(ethylene oxide)-polypropylene oxide)poly(ethylene oxide) block copolymers with cationic surfactants in aqueous solution, MS Bakshi; S Sachar; T Yoshimura; K Esumi, The association behavior of poly(ethylene oxide)-polypropylene oxide)-polyethylene oxide) (PEO-PPO-PEO) block copolymers in aqueous solution with hexadecyltrimethylammonium bromide (HTAB), tetradecyltrimethylammonium bromide (TTAB), and dimethylene bis(decyldimethylammonium bromide) (10-2-10), was studied by fluorescence, viscosity, and Krafft temperature measurements. It has been observed that (EO)(18)(PO)(31)(EO)(18) interacts more strongly than (EO)(2)(PO)(15.5)(EO)(2) and (EO)(2.5)(PO)(31)(EO)(2.5) with HTAB/TTAB due to synergistic interactions. A stronger capability of (EO)(18)(PO)(31)(EO)(18) to interact with cationic surfactants arises from the greater number of electronegative EO units (total 36 EO units) than of (EO)(2)(PO)(15.5)(EO)(2) (total 4 EO units) and (EO)(2.5)(PO)(31)(EO)(2.5) (total 5 EO units). The antagonistic mixing behavior of present triblock polymers has been observed with 10-2-10. A difference in the mixing behavior of the latter from that of HTAB/TTAB has been attributed to its dimeric nature, which may create steric hindrances with triblock polymer components at the head group region in the mixed state. (C) 2004 Elsevier Inc. All rights reserved., 2004年10月, 278, 1, 224, 233, 研究論文（学術雑誌）, 10.1016/j.jcis.2004.05.025

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• 査読あり, 英語, COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, Dodecyltrimethylammonium and Di(dodecyldimethylammonium) bromides interactions with poly (amidoamine) dendrimer, MS Bakshi; A Kaura; RK Mahajan; T Yoshimura; K Esumi, The conductivity (kappa), surface tension (gamma), viscosity (eta), dynamic light scattering (DLS) and Krafft temperature (K-T) measurements of aqueous dodecyltrimethylammonium bromide (DTAB) and di(dodecyldimethylammonium bromide) (12-2-12) with poly (amidoamine) (PAMAM) dendrimers have been carried out at 25 degreesC. From the K data, the apparent critical micelle concentration (acmc) for 12-2-12 and DTAB in aqueous PAMAM and complex forming concentration of PAMAM (C-S) were computed. Both acme and C-S increased with the increase in [PAMAM] and [12-2-12], respectively. The gamma studies indicated a considerable decrease in the gamma value for 12-2-12 in aqueous 0 and 1 G than 0.5 and 1.5 G. However, similar gamma behavior of DTAB in aqueous PAMAM did not discriminate among various generations. From 17 studies, the intrinsic viscosities of 12-2-12 ([eta](12-2-12)) and DTAB ([eta](DTAB)) for 12-2-12 and DTAB in aqueous PAMAM were computed. Both values were higher for 12-2-12 than for DTAB suggesting stronger association in 12-2-12 + PAMAM complex. (C) 2004 Elsevier B.V. All rights reserved., 2004年10月, 246, 1-3, 39, 48, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2004.07.017

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• 査読あり, 英語, J. Jpn. Soc. Colour Mater., Interaction forces Between Glass Surfaces with Adsorption of Quaternary Trimeric Surfactants, 吉村倫一, 2004年10月, 77, 10, 435-440
• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Synthesis and surface properties of anionic gemini surfactants with amide groups, T Yoshimura; K Esumi, Novel anionic gemini surfactants, 1,2-bis(N-beta-carboxypropanoyl-N-alkylamino)ethane (2C(n)enAm; n is hydrocarbon chain length of 6, 8, 10, 12, or 14), with two hydrocarbon chains, two carboxylate groups, and two amide groups, were synthesized by three-step reactions. Their solution properties were characterized by equilibrium and dynamic surface tension, steady-state fluorescence spectroscopy of pyrene, and dynamic light-scattering techniques. The surface tension measurements of 2C(n)enAm give low critical micelle concentrations (cmc), great efficiency in lowering the surface tension, and strong adsorption at air/water interface. Gemini surfactants behave normally with the logarithm of cmc decrease linearly with the chain length. In addition, adsorption and micellization behavior of 2C(n)enAm was estimated by parameter of pC(20), cmc/C-20, and standard free energy (DeltaG(mic)(0) and DeltaG(ads)(0)); they are significantly influenced by hydrocarbon chain length, and the adsorption is promoted more than the micellization as chain length becomes longer. The results of dynamic light-scattering and fluorescence quenching indicate that small micelles of 2C(n)enAm are observed at the concentrations above the cmc, and further large particles are also seen. Further, from the dynamic surface tension measurements, it is found that the shorter hydrocarbon chain length of 2C(n)enAm, the faster the rate of decrease of surface tension. (C) 2004 Elsevier Inc. All rights reserved., 2004年08月, 276, 1, 231, 238, 研究論文（学術雑誌）, 10.1016/j.jcis.2004.03.045

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Physicochemical properties of anionic triple-chain surfactants in alkaline solutions, T Yoshimura; K Esumi, Physicochemical properties of two types of anionic triple-chain surfactants of disodium 2, 10-didecyl-6-dodecyl-3,6,9-triazaundecanedioate (3C(12)dtda) with three hydrocarbon chains and two carboxylate headgroups, and trisodium tris(N-2-ethylamino-N'-2-dodecylcarboxylato)-azane (3C(12)tata) with three hydrocarbon chains and three carboxylate headgroups were characterized by several techniques such as static surface tension, fluorescence spectroscopy, and dynamic and static light-scattering in alkaline solutions at pH 13. 3C(12)dtda shows a much lower critical micelle concentration (cmc) and higher efficiency in lowering the surface tension than 3C(12)tata. 3C(12)dtda also provides a very small occupied area per molecule as compared to 3C(12)tata and packs closely at the interface. The fluorescent intensity ratio of the first to third band in the emission spectra of pyrene for two triple-chain surfactants starts to decrease gradually from around the cmc obtained by the surface tension method, and decreases sharply from the concentration of 10-18 fold cmc. It is also found that the polarity of the triple-chain surfactant micelle is very much lower than that of the single-chain surfactant micelle. The results of dynamic and static light-scattering measurements show the difference behavior in the aggregation process for two triple-chain surfactants; that is, 3C(12)dtda forms large aggregates, and 3C(12)tata forms two aggregates of normal micelle size and a larger one in solution. This indicates that the aggregation states of triple-chain surfactants differ by the number of carboxylate groups, and the large aggregates are derived from the strong attractive interaction between multiple hydrocarbon chains. (C) 2004 Elsevier Inc. All rights reserved., 2004年08月, 276, 2, 450, 455, 研究論文（学術雑誌）, 10.1016/j.jcis.2004.03.069

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Effect of pH on adsolubilization of single and binary organic solutes into a cationic hydrocarbon surfactant adsorbed layer on silica, N Okamoto; T Yoshimura; K Esumi, The adsolubilization behaviors of 2-naphthol, biphenyl, and their binary solutes in the hexadecyltrimethyl ammonium bromide (HTAB) adsorbed layer formed on silica have been studied with solution pH. Two feed concentrations of HTAB are employed: 1.5 and 3.0 mmol dm(-1). At the feed concentration of 1.5 mmol dm(-3) HTAB, most of HTAB are adsorbed on the silica as a monolayer, while a bilayer formation occurs at the feed concentration of 3.0 mmol dm-3. It is found that the adsolubilized amounts of respective single solutes increase with increasing solution pH except acidic region for biphenyl under a constant feed concentration of 2-naphthol (0.4 mmol dm(-3)) and biphenyl (0.047 mmol dm(-3)). The adsolubilization of binary solutes depends on the feed concentration of HTAB; at the low HTAB feed concentration, competitive adsolubilization between 2-naphthol and biphenyl occurs above pH 4.5, while at the high HTAB feed concentration the adsolubilization of biphenyl is enhanced by the incorporation of 2-naphthol over a whole pH region. These behaviors in the adsolubilization are discussed from the surfactant structure of HTAB adsorbed as well as the admicellar partitioning coefficients. (C) 2004 Elsevier Inc. All rights reserved., 2004年07月, 275, 2, 612, 617, 研究論文（学術雑誌）, 10.1016/j.jcis.2004.02.062

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Interactions of quaternary ammonium salt-type gemini surfactants with sodium poly(styrene sulfonate), T Yoshimura; Y Nagata; K Esumi, The interactions of cationic gemini surfactants, 1,2-bis(alkyldimethylammonio)ethane dibromide (m-2-m: m is hydrocarbon chain length, m = 10 and 12), and an anionic polymer, sodium poly(styrene sulfonate) (PSS), have been characterized by several techniques such as tensiometry, fluorescence spectroscopy, and dynamic light scattering. The surface tension of germini surfactant/PSS mixed systems decreases with surfactant concentration, reaching break points, which are taken as critical aggregation concentrations (cac). The surface tension at the cac of mixtures is higher than that of single surfactants, and it is found that at concentrations above the cac, the surfactant molecules are associated with the polymer in the bulk. The 12-2-12/PSS mixed system shows higher surface activity than both 10-2-10/PSS and the monomeric surfactant of dodecyltrimethylammonium bromide/PSS systems. Fluorescence measurements of these mixed systems suggest the formation of a complex with a highly hydrophobic environment in the bulk of the solution. Additionally, dynamic light scattering measurements show that the hydrodynamic diameter of the 12-2-12/PSS mixed system is smaller than that of PSS only at low concentration, indicating interactions between surfactant and polymer. These result from the electrostatic attraction between ammonium and sulfate headgroups as well as the hydrophobic interaction between their hydrocarbon chains. (C) 2004 Elsevier Inc. All rights reserved., 2004年07月, 275, 2, 618, 622, 研究論文（学術雑誌）, 10.1016/j.jcis.2004.03.002

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• 査読あり, 英語, LANGMUIR, Synthesis of gold nanopartieles from an organometallic compound in supercritical carbon dioxide, K Esumi; S Sarashina; T Yoshimura, This article presents the synthesis of gold nanoparticles in a single-phase supercritical fluid carbon dioxide solvent. The gold nanoparticles were formed by the reduction of triphenylphosphine gold(I) perfluorooctanoate with dimethylamineborane. Transmission electron microscopy, X-ray photoelectron spectroscopy, and UV-vis spectroscopy reveal the formation of gold nanoparticles of 1 nm in diameter. A high dispersion stability of the gold nanoparticles in supercritical carbon dioxide can be obtained by binding both triphenylphosphine and fluorocarbon ligands on the surface of the gold nanoparticles., 2004年06月, 20, 13, 5189, 5191, 研究論文（学術雑誌）, 10.1021/la049415e

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• 査読あり, 英語, 色材協會誌, 一般社団法人 色材協会, Adsolubilization of 2-Naphthol by Cationic Multi-Chained Surfactants at Silica/Water Interface, 吉村倫一, シリカへの2-ナフトールの吸着可溶化を陽イオン性多鎖型界面活性剤, ジェミニ型 (10-2-10, 12-2-12) と三鎖型 (10-2-10-2-10, 12-2-12-2-12) を用いて調べた。比較として一鎖型のドデシルトリメチルアンモニウム ブロマイド (DTAB) も用いた。全ての界面活性剤の系において, 界面活性剤の吸着は濃度の増加にともない増え, 飽和に達した。一方, 2-ナフトールの吸着可溶化は界面活性剤の濃度とともに増加し, 最大値を示した後減少した。最大吸着可溶化における界面活性剤の吸着量に対する吸着可溶化量の比の大きさは10-2-10-2-10>2-2-12-2-12>12-2-12=DTAB>10-2-10の順となった。また, 吸着している界面活性剤の炭化水素鎖あたりの比は10-2-10-2-10=12-2-12>12-2-12-2-12=10-2-10となり, DTABの比は他の界面活性剤に比べて著しく大きな値であった。これらの結果は界面活性剤吸着層の充填度により説明される。また, 吸着可溶化に及ぼす界面活性剤の構造の効果についても2-ナフトールのアドミセル分配係数から議論した。, 2004年05月, 77, 5, 207-212, 212, 10.4011/shikizai1937.77.207

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Mixed micellar properties of cationic trimeric-type quaternary ammonium salts and anionic sodium n-octyl sulfate surfactants, T Yoshimura; A Ohno; K Esumi, The properties of quaternary ammonium salt-type cationic trimeric surfactants (m-2-m-2-m, m represents the carbon atom number in alkyl chain lengths of 8, 10, and 12) and oppositely charged anionic monomeric surfactant, sodium n-octyl sulfate (SOS), were characterized by employing several techniques such as static surface tension, fluorescence spectroscopy, and dynamic light-scattering measurements. The critical micelle concentrations (cmc) of m-2-m-2-m were much lower than those of the corresponding dimeric and monomeric surfactants, and decreased with increasing chain length. The addition of SOS to m-2-m-2-m solutions resulted in a further decrease of the cmc. The mixed surfactants showed higher efficiencies in lowering the surface tension than the individual surfactants. The fluorescence measurements suggested the formation of mixed micelles with a hydrophobic environment in the solutions even at lower concentrations. The dynamic light-scatteting stud), indicated the presence of two different kinds of aggregates with different hydrodynamic diameters. The larger one was attributed to the mixed micelle of m-2-m-2-m and SOS. These results indicated a decline of the electrostatic repulsion between cationic head groups through the incorporation of anionic surfactant into the mixed surfactants. (C) 2004 Elsevier Inc. All rights reserved., 2004年04月, 272, 1, 191, 196, 研究論文（学術雑誌）, 10.1016/j.jcis.2003.12.021

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• 査読あり, 日本語, 色材協会誌, 新規Gemini型およびTrimeric型界面活性剤の特性（総説）, 吉村倫一; 江角邦男, 2004年04月, 77, 4, 177-183
• 査読あり, 英語, LANGMUIR, Antioxidant action by gold-PAMAM dendrimer nanocomposites, K Esumi; H Houdatsu; T Yoshimura, Gold-dendrimer nanocomposites were prepared in the presence of poly(amidoamine) (PAMAM)dendrimer (generation 3, 3.5, 5, and 5.5) via reduction of HAuCl4 with sodium borohydride. The average particle size of the gold nanoparticles was independent of the dendrimer concentration, ranging between 3.0 and 4.3 nm in diameter. The catalytic activities of the gold-dendrimer nanocomposites upon elimination of hydroxyl radicals formed in an H2O2/FeSO4 system were examined using a spin-trapping method. The gold-dendrimer nanocomposites exhibited high catalytic activities which were hardly affected by the concentration and the generation of the dendrimer except PAMAM dendrimer 3.5. The highest activity for the gold-PAMAM dendrimer 3.5 nanocomposites was 85 times that of ascorbic acid., 2004年03月, 20, 7, 2536, 2538, 研究論文（学術雑誌）, 10.1021/la036299r

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• 査読あり, 英語, 色材協會誌, 一般社団法人 色材協会, Binary Adsolubilized of Organic Compounds in a Fluorocarbon Surfactant Adsorbed Layer Formed on Titanium Dioxide, 吉村倫一, 二酸化チタンに形成された陽イオン性フッ化炭素界面活性剤吸着層への二種類の有機化合物 (2-ナフトール+ビフェニル;2-ナフトール+1, 3-デクロルベンゼン) の吸着可溶化挙動を水溶液のpHを変えて調べた。2-ナフトール+ビフェニル系において, 2-ナフトールの吸着可溶化量はpH 7までは徐々に増加し, それ以上のpHでは急激に増えた。一方, ビフェニルの吸着可溶化は幅広いpHにおいても観察されなかった。2-ナフトール+1, 3-ジクロルベンゼン系では2-ナフトールの吸着挙動は2-ナフトール+ビフェニル系での2-ナフトールと同様な傾向を示したが, 1, 3-ジクロルベンゼンの吸着可溶化量はpH3から10で徐々に増加した。高いpHでの2-ナフトールの吸着可溶化量の増大は負に帯電したTiO₂と界面活性剤との相互作用の増加ならびに脱水素化2-ナフトールと陽イオン性界面活性剤との相互作用に起因する。2-ナフトール+1, 3-ジクロルベンゼン系での吸着可溶化サイトはアドミセル分配係数から議論された。, 2004年01月, 77, 1, 13-18, 18, 10.4011/shikizai1937.77.13

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• 査読あり, 英語, JOURNAL OF SURFACTANTS AND DETERGENTS, Synthesis and surface-active properties of trimeric-type anionic surfactants derived from tris(2-aminoethyl)amine, T Yoshimura; N Kimura; E Onitsuka; H Shosenji; K Esumi, Trimeric-type anionic surfactants (3C(n)taAm, where n is a hydrocarbon chain length of 8, 10, or 12) with three hydrocarbon chains and three carboxylate headgroups were synthesized from tris(2-aminoethyl)amine, and their properties were investigated by surface tension, electrical conductivity, dynamic and static light-scattering, fluorescence of pyrene, and emulsification power techniques. The critical micelle concentrations (CMC) of 3C(n)taAm were 0.00092-0.00834 mmol dm(-3), and the surface tensions at the CMC were 33.3-39.9 mN m(-1). The areas per molecule occupied by 3C(10)taAm and 3C(12)taAm were extremely small, showing they were highly compact at the air/water interface. In addition, adsorption or micellization behavior of 3C(n)taAm was estimated by parameters such as pC(20) (the efficiency of surface adsorption), CMC/C-20 (the ease of adsorption relative to the ease of micellization), and DeltaG(M)(o) (Gibbs energy of micellization). Dynamic and static light-scattering measurements of 3C(n)taAm showed a hydrodynamic radius of 45-61 nm above the CMC and aggregation numbers of 10-82 at the CMC, respectively. The fluorescence intensity ratio of the first to the third band in the emission spectra of pyrene started to lower from far above the CMC for 3C(8)taAm and 3C(10)taAm, and below the CMC for 3C(12)taAm. This suggests that loose micelles or premicellar aggregates are formed in solutions. Mixtures of aqueous solutions of 3C(n)taAm and toluene formed oil-in-water-type emulsions, and the stabilizing abilities were in the order of 3C(8)taAm > 3C(10)taAm > 3C(12)taAm. The degree of emulsification of 3C(8)taAm remained at 69% after 24 h of standing. Thus, 3C(n)taAm exhibited unique properties superior to monomeric or dimeric surfactants that were significantly influenced by their hydrocarbon chain lengths., 2004年01月, 7, 1, 67, 74, 研究論文（学術雑誌）
• 査読あり, 英語, COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, Adsorption characteristics of poly(amidoamine) and poly (propylene imine) dendrimers on gold, K Esumi; M Ichikawa; T Yoshimura, The adsorption of poly(amidoamine) (PAMAM) and poly(propylene imine) (PPI) dendrimers having different generations from their aqueous solutions on gold electrode has been investigated using a 27 MHz quartz crystal microbalance. The adsorption of PAMAM dendrimers (generation G = 3, 4, and 5) depends on the generation, whereas that of PPI dendrimers (G = 2, 3, and 4) is almost independent on the generation. The occupied area by the dendrimers adsorbed suggests a formation of multilayer of the dendrimers where the number of the layer for PAMAM dendrimers is larger than that for PPI dendrimers. The mechanism for the formation of multilayer is also discussed. (C) 2003 Elsevier B.V. All rights reserved., 2004年01月, 232, 2-3, 249, 252, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2003.11.006

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• 査読あり, 英語, LANGMUIR, Preparation of PAMAM- and PPI-metal (silver, platinum, and palladium) nanocomposites and their catalytic activities for reduction of 4-nitrophenol, K Esumi; R Isono; T Yoshimura, Dendrimer-metal (silver, platinum, and palladium) nanocomposites are prepared in aqueous solutions containing poly(amidoamine) (PAMAM) dendrimers with surface amino groups (generations 3, 4, and 5) or poly(propyleneimine) (PPI) dendrimers with surface amino groups (generations 2, 3, and 4). The particle sizes of the metal nanoparticles obtained are almost independent of the generation as well as the concentration of the dendrimer for both the PAMAM and the PPI dendrimers; the average sizes of silver, platinum, and palladium nanoparticles are 5.6-7.5, 1.2-1.6, and 1.6-2.0 nm, respectively. It is suggested that the dendrimer-metal nanocomposites are formed by adsorbing the dendrimers on the metal nanoparticles. Studies of the reduction reaction of 4-nitrophenol by these nanocomposites show that the rate constants are very similar between PAMAM and PPI dendrimer-silver nanocomposites, whereas the rate constants for the PPI dendrimer-platinum and -palladium nanocomposites are greater than those for the corresponding PAMAM dendrimer nanocomposites. In addition, it is found that the rate constants for the reduction of 4-nitrophenol involving all the dendrimer-metal nanocomposites decrease with an increase in the dendrimer concentrations, and the catalytic activity of dendrimer-palladium nanocomposites is highest., 2004年01月, 20, 1, 237, 243, 研究論文（学術雑誌）
• 査読あり, 英語, 色材協會誌, 一般社団法人 色材協会, Preparation of Gold-Poly(propylene imine)Dendrimer Nanocomposites with UV Irradiation, 吉村倫一, 表面アミノ基を有するポリプロピレンイミンデンドリマー (PPI) (世代2, 3または4) の存在下, UV照射により金ナノ粒子を調製した。紫外可視吸収スペクトル, 動的光散乱法ならびに透過型電子顕微鏡を用いて金-PPIナノコンポジットの生成ならびに構造をしらべた。金イオンの還元はUV照射時間の増加にともない進み, また得られた金ナノ粒子の平均粒子径はデンドリマーの濃度が増えると増加した。金-PPIナノコンポジットの構造はPPI分子が金ナノ粒子に吸着することにより形成されることが示唆された。さらに, 金-PPIナノコンポジットによる4-ニトロフェノールの還元反応における反応定数はPPIデンドリマーの世代ならびに濃度に関係なくほぼ同じであることがわかった。, 2003年12月, 76, 12, 463-468, 468, 10.4011/shikizai1937.76.463

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Morphological change of gold-dendrimer nanocomposites by laser irradiation, K Esumi; K Hayakawa; T Yoshimura, Gold-dendrimer nanocomposites are prepared in aqueous solutions in the presence of poly(amidoamine)dendrimers (PAMAM) (generation 3 and 5) or poly(propyleneimine)dendrimers (PPI) (generation 3 and 4) by wet chemical NaBH4 method. Thus prepared gold-dendrimer nanocomposites are irradiated by laser at 532 nm. UV-vis absorption spectroscopy and transmission electron microscopy reveal that the gold nanoparticles grow with the laser irradiation time as well as the fluence of the laser; in particular, the gold nanoparticles prepared at lower concentrations of PAMAM dendrimer as well as lower generations of PAMAM grow significantly. On the other hand, in the case of PPI dendrimers, the gold nanoparticles hardly grow by irradiation. In addition, dynamic light-scattering measurements show that the laser irradiation markedly promotes the association of the gold-PAMAM G3 dendrimer nanocomposites compared to that of the gold-PAMAM G5 dendrimer nanocomposites, while the sizes of association for the gold-PPI G3, G4 dendrimer nanocomposites hardly change by laser irradiation. (C) 2003 Elsevier Inc. All rights reserved., 2003年12月, 268, 2, 501, 506, 研究論文（学術雑誌）, 10.1016/S0021-9797(03)00598-8

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• 査読あり, 日本語, 色材協会誌, 一般社団法人 色材協会, 表面間力測定による分子吸着層のナノ構造評価（総説）, 酒井健一; 佐田山彩紀; 吉村倫一; 江角邦男, 2003年12月, 76, 12, 495-502, 502, 10.4011/shikizai1937.76.495

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Physicochemical properties of quaternary ammonium bromide-type trimeric surfactants, T Yoshimura; H Yoshida; A Ohno; K Esumi, Trimeric surfactants of quaternary ammonium bromide (m-2-m-2-m, where m is the hydrocarbon chain length of 8, 10, or 12) with three hydrocarbon chains and three hydrophilic groups connected by two ethylene spacer chains were synthesized by the reaction of N, N, N', N",N"-pentamethyldiethylenetriamine and the corresponding alkyl bromide. Their physicochemical properties were characterized by surface tension. static and dynamic light-scattering, and fluorescence spectrum of pyrene techniques. The critical micelle concentrations (cmc's) of m-2-m-2-m shifted to lower concentrations with increasing hydrocarbon chain length, and their values were smaller by about one to three orders of magnitude than those of the corresponding dimeric (m-2-m) and monomeric surfactants (C(m)TAB) with the same hydrocarbon chain length. Of these surfactants, 10-2-10-2-10 showed the greatest efficiency in lowering the surface tension and provided the smallest occupied area per molecule, indicating that it adsorbs more compactly at the air/water interface. In addition, from the static and dynamic light-scattering measurements, the aggregation numbers of the trimeric surfactants at the cmc were very small, and two hydrodynamic diameters above the cmc were observed. (C) 2003 Elsevier Inc. All rights reserved., 2003年11月, 267, 1, 167, 172, 研究論文（学術雑誌）, 10.1016/S0021-9797(03)00694-5

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• 査読あり, 英語, JOURNAL OF PHYSICAL CHEMISTRY B, Interaction Forces on α-Alumina Surfaces with Coadsorption of Anionic/Nonionic Surfactant Mixtures, 吉村倫一, Direct measurement of interaction forces between a-alumina surfaces with coadsorbed anionic sodium dodecyl sulfate (SDS) and nonionic hexaoxyethylenedodecyl ether (C12E6) at pH 3.5 is carried out by colloidal probe atomic force microscopy. The strength of interaction forces is found to be dependent on the initial SDS concentrations, whereas the addition of C12E6 alone causes negligible effects on the interaction. This is due to the absence of attractive interactions between C12E6 molecules and a-alumina. On the other hand, the interaction forces are remarkably different for the simultaneous addition of the two surfactants. At lower C12E6 concentrations the observed repulsion induced by the electric double layer is larger than that in the corresponding single SDS solution, suggesting the stronger SDS adsorption as a consequence of the reduction of the electrostatic repulsion between the ionic headgroups of SDS admicelles. By the further addition of C12E6 a steric stabilizing force is detected from the separation of approximately 5 nm. This is attributed to the formation of a closely packed adlayer comparing with the case of the single SDS admicelles. The effects of sequential addition of C12E6 to the alpha-alumina preadsorbed hydrophobically with SDS are also investigated to understand the complex phenomena that occur at the interface., 2003年11月, 107, 44, 12227, 12232, 研究論文（学術雑誌）, 10.1021/jp0350161

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• 査読あり, 英語, 色材協會誌, 一般社団法人 色材協会, Preparation of Silver-, Platinum-, and Palladium-PAMAM Dendrimer Nanocomposites and Their Catalytic Activities for Reduction of 4-Nitrophenol, 吉村倫一, 金属 (銀, 白金ならびにパラジウム) -デンドリマーナノコンポジットを末端官能基がカルボキシル基またはアミノ基のポリアミドデンドリマー (世代;1.5, 3.0, 3.5, 4.0, 5.0ならびに5.5) を用いて調製した。平均粒子直径は銀粒子で5-7nm, 白金で1-2nm, パラジウムで約2nmとなり, デンドリマーの濃度に依存したが世代の影響は小さかった。とくに, 末端官能基としてカルボキシル基を有するデンドリマーを用いたときに安定な金属-デンドリマーナノコンポジットがより低いデンドリマー濃度で得られた。また, 金属-デンドリマーナノコンポジットは金属粒子表面をデンドリマー分子が被うことにより生成することが示唆された。金属-デンドリマーナノコンポジットによる4-ニトロフェノールの還元反応の速度定数はデンドリマーの世代, 濃度または末端官能基の種類に依存した。三種類の金属-デンドリマーナノコンポジットにおいてパラジウムーデンドリマーナノコンポジットがもっとも高い触媒活性を示した。, 2003年11月, 76, 11, 421-427, 427, 10.4011/shikizai1937.76.421

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• 査読あり, 英語, 色材協會誌, 一般社団法人 色材協会, Interactions Between Thiol-Modified Gold Nanoparticles and a Cationic Polyelectrolyte, 吉村倫一, メルカプト酢酸で表面修飾した金ナノ粒子と陽イオン性高分子であるポリジメチルジアリルアンモニウムクロライド (PDC) との相互作用を調べた。比較として界面活性剤ヘキサデシルトリメチルアンモニウムブロマイド (HTAB) を用いて修飾した金ナノ粒子との相互作用も検討した。二つの修飾した金ナノ粒子の平均直径は5.7と12.9nmであった。大部分の実験は修飾した金ナノ粒子の濃度を固定し, PDCの濃度を変化させpH3と8で行った。可視紫外分光ならびに透過電子顕微鏡測定から, pH8において修飾した金ナノ粒子 (5.7nm) はPDCの添加濃度の増加にともない徐々に凝集する。一方, 修飾した金ナノ粒子 (12.9nm) はPDCの低い濃度で凝集するが, PDC濃度が高くなると金ナノ粒子はよく分散した。pH3では二つの金ナノ粒子ともPDCの濃度増加にともない分散-凝集-再分散を示した。これらの相互作用はおもに負電荷を帯びた金ナノ粒子と正電荷を帯びたPDCとの静電的な引力によるものと考えられ, また, pHにも影響される。修飾した金ナノ粒子とHTABとの系においては金ナノ粒子はHTAB濃度の増加にともない分散-凝集-再分散を示した。再分散は金ナノ粒子表面でのHTABの二層吸着層の形成によるものsと考えられる。, 2003年11月, 76, 11, 428-433, 433, 10.4011/shikizai1937.76.428

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• 査読あり, 英語, COLLOIDS AND SURFACES B-BIOINTERFACES, Antioxidant-potentiality of gold-chitosan nanocomposites, K Esumi; N Takei; T Yoshimura, Gold nanoparticles were prepared in the presence of chitosan via reduction of HAuCl4 with sodium borohydride. The average particle size of gold nanoparticles was significantly affected with the concentration of chitosan added and was ranged between 6 and 16 nm. The gold-chitosan nanocomposites are formed by adsorbing chitosan molecules on the gold nanoparticles. The catalytic activity of gold-chitosan nanocomposites upon elimination of hydroxyl radicals formed in an H2O2/FeSO4 system was examined using a spin-trapping method. The catalytic activity increased with the concentration of chitosan added and showed a maximum and then decreased with a further concentration of chitosan added, although a strict correlation between the average diameter of gold and the catalytic activity was not found. In addition, the activity of gold-chitosan was 80 times higher than that of ascorbic acid, which is well known as an antioxidant. (C) 2003 Elsevier B.V. All rights reserved., 2003年10月, 32, 2, 117, 123, 研究論文（学術雑誌）, 10.1016/S0927-7765(03)00151-6

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• 査読あり, 英語, LANGMUIR, Multilayer formation using oppositely charged gold- and silver-dendrimer nanocomposites, K Esumi; S Akiyama; T Yoshimura, 2003年09月, 19, 18, 7679, 7681, 研究論文（学術雑誌）, 10.1021/la034777s

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• 査読あり, 英語, LANGMUIR, Preparation of gold-dendrimer nanocomposites by laser irradiation and their catalytic reduction of 4-nitrophenol, K Hayakawa; T Yoshimura; K Esumi, Gold nanoparticles were prepared in the presence of poly(amidoamine) (PAMAM) dendrimers (generations 3.0 and 5.0) or poly(propyleneimine) (PPI) dendrimers (generations 3.0 and 4.0) with surface amino groups by laser irradiation. UV-visible absorption, dynamic light scattering, and transmission electron microscopy have been used to study the formation and structure of the nanocomposites. The reduction of Au(3+) ions proceeded with an increase of the irradiation time, and the average diameters of the gold nanoparticles obtained tended to decrease with an increase of the dendrimer concentration. It is suggested that the dendrimers are adsorbed on the nanoparticles as a monolayer. Studies of the reduction reaction of 4-nitrophenol by the gold nanoparticles with NaBH(4) reveal that the rate constants for PPI dendrimers are higher than those for PAMAM dendrimers, whereas the size of the PPI dendrimer of the same generation is considerably smaller than that of the PAMAM dendrimer., 2003年06月, 19, 13, 5517, 5521, 研究論文（学術雑誌）, 10.1021/1a0343391

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• 査読あり, 英語, LANGMUIR, Physicochemical properties of ring-type trimeric surfactants from cyanuric chloride, T Yoshimura; K Esumi, 2003年04月, 19, 8, 3535, 3538, 研究論文（学術雑誌）, 10.1021/la026762k

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• 査読あり, 英語, COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, Physicochemical properties of aqueous mixed solutions of sugar-persubstituted poly(amidoamine)dendrimers and bovine serum albumin, T Chiba; T Yoshimura; K Esumi, The interactions of bovine serum albumin (BSA) with sugar-persubstituted poly(amidoamine)dendrimers (SB, generation 3 and 5) have been studied using several techniques including interfacial rheometer. The sample solutions are prepared by mixing SB5 or SB3 to BSA under a fixed concentration of BSA. In BSA-SB5 system, mixed solutions become turbid due to the formation of aggregates between BSA and SB5 by adding a small amount of SB5, but a further addition of SB5 renders the aggregates redispersed. These results are reflected in the changes of surface tension, interfacial rheology, and circular dichroism (CD) spectra for BSA-SB5 system. On the other hand, BSA-SB3 system does not show significant physicochemical properties due to a weak interaction between BSA and SB3. (C) 2002 Elsevier Science B.V. All rights reserved., 2003年03月, 214, 1-3, 157, 165, 研究論文（学術雑誌）
• 査読あり, 英語, COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, Interactions of fluorocarbon-modified poly(acrylic acid) with a cationic fluorocarbon surfactant, F Kobayashi; T Yoshimura; K Esumi, The physicochemical properties of mixed systems of fluorocarbon-modified poly(acrylic acid) (FA) with a cationic fluorocarbon surfactant, bis(2-hydroxyethyl)(2-hydroxy-3-perfluoro-octylpropyl)methylammonium chloride (DEFUMAC), have been investigated by surface tension, fluorescence, solubility, and F-19 NMR spin-lattice relaxation measurements. The result obtained from the surface tension measurement indicates that surface DEFUMAC-FA complexes are formed by strong electrostatic attraction at pH 10, while they are formed by hydrogen bond at pH 4. However, hydrophobic interaction is hardly observed at both pHs. In the bulk properties estimated from fluorescence and solubility measurements, DEFUMAC-FA complexes exhibit large solubility capacity for fluorocarbon compounds when the content of fluorocarbon in FA increases. Moreover, the result obtained from the spin-lattice relaxation time measurement suggests that the mobility of hydrophobic end group of DEFUMAC for DEFUMAC-FA complex at pH 10 is more restricted than that at pH 4. (C) 2002 Elsevier Science B.V. All rights reserved., 2003年03月, 214, 1-3, 271, 278, 研究論文（学術雑誌）
• 査読あり, 英語, COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, Preparation of noble metal nanoparticles in supercritical carbon dioxide, A Kameo; T Yoshimura; K Esumi, Silver, palladium, and silver-palladium nanoparticles have been prepared by reduction of silver acetylacetonate and palladium acetate with dimethylamine-borane in the presence of a fluorinated surfactant (FOMBLIN HC/P2-1000) in supercritical carbon dioxide. The sizes of silver and palladium nanoparticles increases with increasing concentrations of both the soluble precursors and FOMBLIN. The size of silver nanoparticles obtained is 3-12 nm, while that of palladium nanoparticles is 3-6 nm. For preparation of silver-palladium nanoparticles, the particle size is ranged between 4 and 5 nm and dependent on the feed molar ratio of palladium acetate. It is found that silver-palladium nanoparticles consist of a core-shell structure with enriched palladium in the surface. (C) 2002 Elsevier Science B.V. All rights reserved., 2003年03月, 215, 1-3, 181, 189, 研究論文（学術雑誌）
• 査読あり, 英語, LANGMUIR, Direct Force Measurements Between α-Alumina Surfaces with Adsorption of Anionic Surfactant/Polymer Mixtures, 吉村倫一, Direct measurements of interaction forces between alpha-alumina surfaces with coadsorbed anionic surfactant sodium dodecyl sulfate (SDS) and anionic polyelectrolyte poly(sodium 4-styrenesulfonate) (PSS) at pH 3.5 are carried out by colloidal probe atomic force microscopy. It is found that in aqueous PSS solutions the interaction forces are dependent on the initial PSS concentration. At low PSS concentration the electrostatic repulsion initially present is neutralized, resulting in a weak attraction between the surfaces, while as the concentration is increased further, repulsive forces reappear due to the additional adsorption of PSS on the surface. The adsorbed PSS adopts a relatively flat conformation at all PSS concentrations investigated. On the other hand, the interaction forces are dramatically different for the simultaneous addition of SDS and PSS: the force profile for the coaddition comes progressively close to that for the addition of SDS alone with increasing SDS concentration. This is attributed to the fact that SDS plays a key role for the coadsorption of SDS and PSS over a high SDS concentration region. The dispersion stability and zeta potential of alpha-alumina suspensions are evaluated for comparison with the resultant forces, and a good correlation is obtained between them. The effects of sequential addition of SDS and PSS are also investigated., 2003年02月, 19, 4, 1203, 1208, 研究論文（学術雑誌）, 10.1021/la026388o

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• 査読あり, 英語, 色材協會誌, 一般社団法人 色材協会, Preparation of Gold Nanoparticles Using Poly(amidoamine)Dendrimers as Stabilizer and Their Catalytic Reduction of 4-Nitrophenol, 吉村倫一, 種々の末端基 (メチルエステル基, アミノ基, カルボキシル基, 糖鎖) をもち, 世代の異なるポリアミドアミンデンドリマーを用いて水系で金ナノ粒子を調製した。得られた平均粒子径は2-6nmでデンドリマーと金イオンの割合ならびにデンドリマーの世代により変化した。4-ニトロフェノールの金ナノ粒子を用いたNaBH₄還元反応から反応定数は添加デンドリマー濃度ならびにデンドリマーの世代に依存した。さらに, 反応定数に及ぼすデンドリマーの末端基の効果はカルボキシル基>アミノ基>糖鎖>メチルエステル基の順となった。これらの結果はデンドリマー-金ナノコンポジットの構造に起因すると考えられる。, 2002年12月, 75, 12, 561-567, 567, 10.4011/shikizai1937.75.561

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Effects of various thiol molecules added on morphology of dendrimer-gold nanocomposites, K Satoh; T Yoshimura; K Esumi, Interactions between poly(amidoamine) dendrimer (PAMAM)gold nanocomposites and alkanethiols and between the former nanocomposites and thiol-modified poly(amidoamine) dendrons in ethyl acetate were investigated by adding alkanethiols, such as 1-propanethiol and 1,3-propanedithiol, and thiol-modified poly(amidoamine) dendrons, generations 0.5 and 2.5 (G0.5-SH and G2.5-SH). The PAMAM dendrimers with surface methyl ester groups used were generations 1.5 and 5.5 (G1.5 and G5.5). The mean particle sizes of PAMAM-gold nanocomposites were about 2.1 for G1.5 and 2.4 nm for G5.5. In both nanocomposite systems where 1-propanethiol and 1,3-propanedithiol were added, the mean particle size was about 4 run, twice that of the systems where these thiols were not added. Increasing the addition of 1,3-propanedithiol made the average particle size smaller for both nanocomposites systems. To compare with alkanethiol, thiol-modified poly(amidoamine) dendron with a highly branched structure on one side was synthesized. Using G2.5-SH as a protective agent, dendron-gold nanocomposites with mean diameters of 3 to 4 nm were obtained. The difference in particle size was seen only when the combination of PAMAM-gold nanocomposites and thiol-modified dendron was less sterically dense, modified dendron (G0.5-SH). The mechanisms for morphology changes in the dendrimer-gold nanocomposites by the addition of these thiols are discussed. (C) 2002 Elsevier Science (USA)., 2002年11月, 255, 2, 312, 322, 研究論文（学術雑誌）, 10.1006/jcis.2002.8585

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Physicochemical properties of quaternized poly(amidoamine) dendrimers with four octyl chains, T Yoshimura; J Fukai; H Mizutani; K Esumi, A cationic dendrimer-type tetrameric surfactant (C(8)qbG0) with four octyl chains and four ammonium groups was synthesized by the reaction of poly(amidoamine) dendrimers with generation of zero and glycidyldimethyloctylammonium bromide. The physicochemical properties Of C(8)qbG0 and of their mixtures with sodium dodecyl sulfate (SDS) were characterized by investigating surface tension, electrical conductivity, fluorescence of pyrene, and dynamic light-scattering. The critical micelle concentration (cmc) Of C(8)qbG0 was 13 mmol dm(-3) at the concentration of one terminal group and the surface tension at the cmc attained 34 mN m(-1). The occupied area of C(8)qbG0 was 1.94 nm(2) molecule(-1), indicating that the tetrameric dendrimers adsorb widely at the air/water interface. The fluorescence intensity ratio of the first-to-third band in the emission spectra of pyrene for C(8)qbG0 decreased from around the cmc obtained by the surface tension measurement. The hydrodynamic radius of C(8)qbG0 determined by dynamic light-scattering was about 1.3 nm. The addition of SDS to the aqueous solutions Of C(8)qbG0 enhanced the surface activities; the mixtures exhibited lower cmc, lower surface tension, and higher solubilization of pyrene than SDS alone. It was found that the mixtures Of C(8)qbG0 and SDS form large aggregates due to the interactions between their alkyl chains as well as hydrophilic groups. (C) 2002 Elsevier Science (USA)., 2002年11月, 255, 2, 428, 431, 研究論文（学術雑誌）, 10.1006/jcis.2002.8626

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• 査読あり, 英語, 色材協會誌, 一般社団法人 色材協会, Highly Efficient Adsolubilization of 2-Naphthol on Alumina by Anionic and Nonionic Surfactant Mixtures, 吉村倫一, 界面活性剤混合系 (陰イオン性、ドデシル硫酸ナトリウム、SDS;非イオン性、ヘキサオキシエチレンデシルエーテル、C₁₀E₆;ヘキサオキシエチレンドデシルエーテル、C₁₂E₆) を用いてアルミナ粒子への2一ナフトールの吸着可溶化をしらべた。界面活性剤の吸着ならびに吸着可溶化は非イオン性界面活性剤の濃度を固定し、SDS濃度を変化させて行った。SDS/C₁₀E₆とSDS/C₁₂E₆の両系において2-ナフトールの吸着可溶化量は非イオン性界面活1生剤の固定濃度の増加とともに増加し、最大を示した後、減少した。2-ナフトールの吸着可溶化量はSDS/C₁₀E₆およびSDS/C₁₂E₆系はSDS単独系にくらべて大きくなった。さらに、吸着した界面活性剤分子あたりの2-ナフトール分子の割合を吸着可溶化効率として最大吸着可溶化量でくらべるとSDS/C₁₂E₆系はSDS/C₁₀E₆系より高い吸着可溶化効率となった。この効率の違いは非イオン性界面活性剤の炭化水素鎖長に影響される混合吸着層の性質に寄与することが考えられる。, 2002年11月, 75, 11, 513-518, 518, 10.4011/shikizai1937.75.513

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• 査読あり, 英語, 色材協會誌, 一般社団法人 色材協会, Preparation of PAMAM Dendrimer-Gold Nanocomposites in Poly(N-isopropylacrylamide)Gel, 吉村倫一, 金ナノ粒子をポリアミドアミンデンドリマー-ポリN-イソプロピルアクリルアミドゲル中で調製した。デンドリマーは表面官能基がアミノ基の世代5, メチルエステル基の世代5.5とカルボキシル基の世代5.5を用いた。表面官能基がアミノ基とメチルエステル基をもつデンドリマーを用いた場合, 直径3-4nmの比較的粒度分布の小さい金ナノ粒子が得られた。一方, 表面官能基にカルボキシル基をもつデンドリマーではより大きなかつ粒度分布の広い金ナノ粒子が得られた。金ナノ粒子の生成に及ぼすゲルマトリックス中でのデンドリマーの役割について議論した。, 2002年10月, 75, 10, 470-473, 473, 10.4011/shikizai1937.75.470

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Comparison of PAMAM-Au and PPI-Au nanocomposites and their catalytic activity for reduction of 4-nitrophenol, K Esumi; K Miyamoto; T Yoshimura, Dendrimer-Au nanocomposites are prepared in aqueous solutions using poly(amidoammine)dendrimers (PAMAM) (generation 2, 3, and 5) and poly(propyleneimine)dendrimers (PPI)(generation 2, 3, and 4) by wet chemical NaBH4 method. The Au nanoparticles thus obtained are 2-4 nm in diameter for both dendrimers and no generation dependence on the particle size is observed, whereas the generations of the dendrimers are increased as stabilization of Au-nanoparticles is achieved with lower dendrimer concentrations. Studies of the reduction reaction of 4-nitrophenol using these nanocomposites show that the rate constants for the PAMAM dendrimers (generations 2 and 3) are higher than those for the PPI dendrimers (generations 2 and 3), while a distinct difference in the rate constants is not seen for the PAMAM dendrimer (generation 5) or the PPI dendrimer (generation 4). In addition, the rate constants for the reduction of 4-nitrophenol involving all the dendrimers decrease with increases in dendrimer concentrations. (C) 2002 Elsevier Science (USA)., 2002年10月, 254, 2, 402, 405, 研究論文（学術雑誌）, 10.1006/jcis.2002.8580

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Direct force measurements between adlayers consisting of poly(amidoamine) dendrimers with primary amino groups or quaternary ammonium groups, K Sakai; S Sadayama; T Yoshimura; K Esumi, Adsorption of poly(amidoamine) generation 3 (PAMAM G3) dendrimer with surface amino groups or PAMAM GO dendrimer with quaternary ammonium groups (C8qbG0) onto glass has been studied by colloidal probe atomic force microscopy. The adlayer-adlayer interactions for these adsorbates are quite different despite the fact that they are almost equal in the hydrodynamic radius. In aqueous PAMAM G3 dendrimer solutions the electrostatic repulsion is predominant. The conformation of the adsorbed layer is flat and the protrusion of the individual dendrimers is negligible. On the other hand, C8qbG0 behaves as a surfactant and the layered structure of C8qbG0 is expected to be a patchy bilayer. Dispersion stability of silica suspensions with the adsorption of these dendrimers can be correlated with the force data obtained. (C) 2002 Elsevier Science (USA)., 2002年10月, 254, 2, 406, 409, 研究論文（学術雑誌）, 10.1006/jcis.2002.8601

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• 査読あり, 英語, LANGMUIR, Simultaneous adsorption of poly(1-vinylpyrrolidone-co-acrylic acid) and sodium dodecyl sulfate at alumina/water interface, K Sakagami; T Yoshimura; K Esumi, The simultaneous adsorption of poly(1-vinylpyrrolidone-co-acrylic acid) (PVcA) and sodium dodecyl sulfate (SDS) on positively charged alumina particles is carried out at pH 5.2 by measuring the amount of PVcA and SDS adsorbed, zeta potential, and sedimentation rate of alumina suspensions. In addition, conformation of PVcA and SDS adsorbed using their corresponding spin-labeled ones is estimated. The amount of PVcA adsorbed increases sharply and becomes a plateau with an increase of PVcA concentration, while a typical adsorption isotherm of SDS is obtained. In the simultaneous adsorption of PVcA and SDS under fixed initial concentrations of PVcA, the amount of PVcA adsorbed increases and reaches a maximum, and then decreases with SDS concentration. The enhancement in the adsorption is due to the interaction between SDS and PVcA as confirmed by surface tensiometry. The dispersion stability of alumina suspensions by the simultaneous adsorption of PVcA and SDS is considerably high compared with that by SDS adsorption alone. The high dispersion stability is due to the extended conformation of the adsorbed PVcA and the electrostatic repulsion force. Further, the mobility of SDS molecules in the PVcA-SDS adsorbed layer is found to be more restricted than that in the SDS adsorbed layer alone., 2002年08月, 18, 16, 6049, 6053, 研究論文（学術雑誌）, 10.1021/la0257236

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• 査読あり, 英語, JOURNAL OF SURFACTANTS AND DETERGENTS, Preparation and surface-active properties of telomer-type anionic surfactants from maleic anhydride, T Yoshimura; Y Koide; H Shosenji; K Esumi, Maleic acid alkyl ester and N-alkyl maleamic acid monomers (R(n)Ma and R(n)MaAm; n is alkyl chain length; n = 6, 8, 10, 12, 14) were synthesized by the reaction of maleic anhydride with alkyl alcohol or alkylamine. The telomerization of R(n)Ma or R(n)MaAm in the presence of alkanethiol as a chain transfer agent gave telomer-type anionic surfactants (xR(n)Ma, xR(n)MaAm; x is total average number of alkyl chains; x = 2.8-3.3) having multialkyl chains and multicarboxylate groups. Their surface-active properties were investigated by several techniques such as surface tension, foaming property, and emulsification power measurements. Critical micelle concentrations (CIVIC) of xRnMa were 1/110-1/14 of those of RnMa with the same alkyl chain length. xRnMa and xRnMaAm gave higher efficiencies in lowering the surface tension than RnMa and RnMaAnn in aqueous solutions. In particular, the surface tension of 3.2R(12)MaAm was 24.4 mN m(-1) at the CMC. Foaming abilities and foam stabilities of xR(n)Ma and xR(n)MaAm were higher than those of R(n)Ma and R(n)MaAm. The addition of 300 ppm of Ca2+ to the aqueous solutions rendered the telomers less surface active. Shaking the aqueous solutions of telomers with toluene emulsified them. The highly stable oil-in-water type emulsion was formed by using 3.0R(10)MaAm and 3.2R(12)MaAm, and the degree of emulsification was kept at a level of about 80% after 60 min of standing. Thus, telomer-type surfactants showed excellent surface activities that were superior to the corresponding monomers as well as to conventional surfactants. The relationship between alkyl chain length of the telomers and the properties of surface tension, foaming, and emulsification was unclear., 2002年07月, 5, 3, 257, 262, 研究論文（学術雑誌）
• 査読あり, 英語, LANGMUIR, Interaction Forces on α-Alumina Surfaces with Coadsorbed Anionic Surfactant and Nonionic Polymer, 吉村倫一, Direct measurements of interaction forces between a-alumina surfaces with coadsorbed anionic surfactant (sodium dodecyl sulfate (SDS) or lithium perfluorooctanesulfonate (LiFOS)) and nonionic polymer poly(vinylpyrrolidone) (PVP) at pH 3.5 are carried out by colloidal probe atomic force microscopy. In aqueous SDS solutions, the strength of interaction forces is found to depend on the initial SDS concentration, whereas in PVP solutions, the electric double layer interaction is completely screened due to the flat conformation of PVP on alpha-alumina. The interaction forces are dramatically different for the coaddition of SDS and PVP: electrostatic repulsion is observed above the critical aggregation concentration, and virtually no steric hindrance due to adsorbed polymer chains can be detected. These coaddition effects are attributed to the flat conformation of the adsorbed PVP and the formation of SDS-PVP surface complexes as confirmed by surface tensiometry. The LiFOS-PVP system exhibits characteristics similar to those of the SDS-PVP system, except that the repulsion between adsorbed LiFOS layers is remarkably weak at concentrations above its critical micelle concentration. The effects of sequential addition of SDS and PVP are also investigated., 2002年05月, 18, 10, 3993, 3998, 研究論文（学術雑誌）, 10.1021/la011786x

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• 査読あり, 英語, Journal of Oleo Science, Surface Activities of Mixtures of Partially-Quaternized 2-Vinylpyridine Telomers and Cationic Gemini Surfactant, Tomokazu Yoshimura; Kosuke Kawashima; Yoshifumi Koide; Hideto Shosenji; Kunio Esumi, The surface activities of mixed surfactants of partially-quaternized 2-vinylpyridine telomers (xRn-2VPQ, x is the total number of alkyl chains, n is the alkyl chain length) and monomeric alkyltrimethylammonium bromide (1RnQ) or gemini 1, 2-bis(alkyldimethylammonio)ethane dibromide (2RnenQ) were investigated at pH 2 by surface tension, foaming property, interfacial tension and emulsification power. The mixed critical micelle concentrations (cmcs) were intermediate between the pure component xRn-2VPQ and 1RnQ or 2RnenQ. xRn-2VPQ / 2RnenQ system was higher efficiencies in lowering the surface tension than xRn-2VPQ / 1RnQ. The surface tension was influenced by the alkyl chain length of binary surfactants and the mole fraction (α) of xRn-2VPQ. In particular, 2.0R10-2VPQ / 2R10enQ system with α = 0.50 showed the lowest surface tension. The mixtures of two cationic multialkylated surfactants improved the foaming properties as compared with the pure component cationic surfactants. The similar trends in the surface tension and the foaming properties were observed for the lowering abilities of the interfacial tension at the water / toluene interface and emulsion stabilities. © 2002, Japan Oil Chemists’ Society. All rights reserved., 2002年, 51, 4, 221, 227, 研究論文（学術雑誌）, 10.5650/jos.51.221

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• 査読あり, 英語, Journal of Oleo Science, Preparation and Surface-Active Properties of N-Alkyl Maleamic Acid Telomer Type Surfactants Having Several Hydrocarbon Chains, Tomokazu Yoshimura; Yoshifumi Koide; Hideto Shosenji; Kunio Esumi, Telomerization of N-alkyl maleamic acid monomer (RnMaAm, n is the alkyl chain length n=6-14), which was synthesized by reaction of maleic anhydride with alkylamine, in the presence of alkanethiol as a chain transfer agent gave the telomers (xRnMaAm, x is total number of alkyl chains x=2.9-3.2) in 60-90 % yields. The surface-active properties such as surface tension, foaming property and emulsion stability were examined in water as well as in hard water containing 300 ppm of Ca2+. The critical micelle concentrations (cmcs) of 2.9-3.2RnMaAm telomers were 1/142-1/42 of those of RnMaAm monomers with the same alkyl chain length. The surface tensions of aqueous solutions of RnMaAm monomers and 2.9-3.2RnMaAm telomers were 30-35 and 24-32 mN m-1, respectively. The addition of Ca2+ to the aqueous solutions of 2.9-3.2RnMaAm lowered the cmc, while gave a low efficiency at reducing the surface tension. Of the telomers, 3.0R12MaAm gave the highest foaming ability and the highest foam stability in water. Shaking of the mixtures of organic solvent and the aqueous solutions of xRnMaAm telomers formed oil-in-water type emulsions. The emulsion stabilities were in the orders of toluene > n-octane > n-dodecane > n-hexadecane > kerosene as an oil phase. The highly emulsions for toluene or n-dodecane were formed by using 3.0R8MaAm and 3.0R10MaAm. The aqueous solutions of RnMaAm monomers and 2.9-3.2RnMaAm telomers gave interfacial tension of 8-10 and 4-6 mN m-1, respectively, for the interface with toluene. Thus, N-alkyl maleamic acid telomer type anionic surfactants having several alkyl chains showed greater surface activities than the corresponding monomeric monomers as well as the conventional surfactants. © 2002, Japan Oil Chemists’ Society. All rights reserved., 2002年, 51, 4, 229, 236, 研究論文（学術雑誌）, 10.5650/jos.51.229

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• 査読あり, 英語, JOURNAL OF SURFACTANTS AND DETERGENTS, Synthesis and Properties of N-(α-Carboxyalkyl)acrylamide Telomer-Type Surfactants Having Multihydrocarbon Chains, 吉村倫一, N-(alpha-Carboxyalkyl)acrylamide telomer-type surfactants (xC(n-1)AmAc where n is alkyl chain length = 6, 8,10,12; and x is degree of polymerization = 3.3-13.1) were synthesized by the telomerization of monomer (Cn-1AmAc) in the presence of the corresponding alkanethiol as a chain transfer agent and then investigated for their surface-active properties. xC(n-1)AmAc telomers lowered the surface tension of aqueous solutions that were at pH 9-10. The critical micelle concentrations (CMC) of the telomers were lower than those of the monomers with the same alkyl chain length, and the CIVIC values shifted to lower concentrations with both increasing alkyl chain length and polymerization degree. xC(9)AmAc with x = 3.3-6.3 gave the highest efficiencies in lowering the surface tension. The cross-sectional molecular areas per molecule of xC(n-1)AmAc telomers were smaller than the values estimated on the assumption that they are assemblies of Cn-1AmAc monomer units. The foaming abilities and the foam stabilities were both in the orders of xC(7)AmAc > xC(9)AmAc > xC(5)AmAc > xC(11)AmAc. Mixtures of aqueous solutions of xC(n-x)AmAc telomers and toluene formed oil-in-water emulsions. The emulsion-stabilizing abilities were in the orders of xC(7)AmAc > xC(5)AmAc > xC(9)AmAc = xC(11)AmAc. The addition of Ca2+ to the mixed solutions of telomers and toluene resulted in formation of water-in-oil type emulsions. Thus, the surface-active properties of the telomers were influenced significantly by the alkyl chain length and the polymerization degree of the telomers. In addition, these properties could be correlated with the hydrophilic-lipophilic balance (HLB); the highest surface activities were observed by using xC(n-1)AmAc with HLB of 14-18., 2002年04月, 5, 2, 159, 164, 研究論文（学術雑誌）
• 査読あり, 英語, Colloids Surf., B, Effect of Dilution on Aqueous Dispersion of Drug Particles, 吉村倫一, 2002年02月, 27, 2-3, 177-180
• 査読あり, 日本語, 色材協会誌, コンプレキサン系Trimeric型界面活性剤の合成と物性（総説）, 吉村倫一; 鬼束優香; 江角邦男, 2002年02月, 75, 2, 75-81
• 査読あり, 日本語, 色材協会誌, テロマー系多鎖型界面活性剤の合成と物性（総説）, 吉村倫一; 江角邦男, 2001年11月, 74, 11, 563-568
• 査読あり, 英語, Journal of Oleo Science, Preparation and Surface Activities of Zwitterionic Surfactants Derived from Cotelomers of 4-Vinylpyridine and Methyl Acrylate, Tomokazu Yoshimura; Rinko Tokunaga; Hideto Shosenji; Kunio Esumi, Cotelomer type zwitterionic surfactants having multi-hexyl chains and multi-carboxylate and multi-pyridinium functions (R6S-zR6VPQ-wVP-yAA, w and y mean the number of 4-vinylpyridine and sodium acrylate, respectively z means number of hexyl chains by quaternization) were prepared by quaternization and hydrolyses of cotelomers, which were prepared by cotelomerization of 4-vinylpyridine and methyl acrylate in presence of hexanethiol, and examined for their surface activities. Critical micelle concentration (cmc) of zwitterionic cotelomers shifted to lower concentration with increasing number of hexyl chains. The cmcs of R6S-zR6VPQ-wVP-yAA with z of 2.1-3.8 were from one 110 th to one 4 th of those of the corresponding cationic cotelomers. Zwitterionic cotelomers gave surface tension of 40-44 mN m-1 at the cmc. The increase of number of hexyl chains in R6S-zR6VPQ-wVP-2.3AA series reduced the surface activities. Vigorous shaking of the mixtures of water and chloroform solution of zwitterionic cotelomers formed oil-in-water type emulsion. Highly stable emulsion was formed by using R6S-zR6VPQ-wVP-2.3AA with z of 1.4-2.1 and the degrees of emulsification were kept at the level of 60-70% after 360 min of standing. Zwitterionic cotelomers gave interfacial tension of 2-4 mN m-1 at the water-chloroform interfaces and oriented themselves easier than equimolar mixtures of cationic cotelomer and anionic cotelomer. © 2001, Japan Oil Chemists' Society. All rights reserved., 2001年, 50, 6, 467, 473, 研究論文（学術雑誌）, 10.5650/jos.50.467

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• 査読あり, 英語, Journal of Oleo Science, Preparation and Surface-Active Properties of Complexanetype Trimeric Surfactants from Tris(2-aminoethyl)amine, Emika Onitsuka; Tomokazu Yoshimura; Yoshifumi Koide; Hideto Shosenji; Kunio Esumi, Complexane-type trimeric surfactants of tris(1-carboxyalkyl-2-aminoethyl)amine (3Rntata n means alkyl chain length, n = 6-14) having three alkyl chains and three hydrophilic groups were prepared by the reaction of tris(2-aminoethyl)amine and 2-bromoalkanoic acid and examined for surface activities such as surface tension, emulsification and interfacial tension. Critical micelle concentration (cmc) of 3Rntata shifted to lower concentration with increasing alkyl chain length. The cmcs of 3Rntata with n of 10-14 were lower by about 1-2 orders of magnitude than those of complexane-type monomeric surfactant of 2-aminoalkanoic acid (RnNAc) and dimeric surfactant of N, N″-bis(1-carboxyalkyl)diethylenetriamine (2Rndtda) with the same alkyl groups. In the case of R12, 3Rntata gave about twice cmc of trimeric surfactant of (N-1-carboxyalkyl-2-aminoethyl)alkyllamine (3Rndtda) having three alkyl chains and two hydrophilic groups. Surface tension at each cmcs of 3R10tata, 3R12tata and 3R14tata was 33.0, 26.9 and 29.6 mN m-1, respectively. 3R12tata and 3R14tata gave more efficient in lowering the surface tension than RnNAc and 2Rndtda. The values of cross-sectional molecular area (A) of 3Rntata with n of 10-14 were 42-75 Å2. They were extremely small in comparison with three times of A of RnNAc. The aqueous solutions of 3Rntata were emulsified by shaking with toluene. Highly stable oil-in-water type emulsion was formed by using 3Rntata with n of 10-14 and the degree of emulsification was kept 60% after 20 h. Interface between the aqueous solutions of 3R10tata, 3R12tata and 3R14tata and toluene gave the interfacial tension of 1, 1 and 6 mN m-1, respectively. © 2001, Japan Oil Chemists' Society. All rights reserved., 2001年, 50, 3, 159, 164, 研究論文（学術雑誌）, 10.5650/jos.50.159

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• 査読あり, 英語, Journal of Oleo Science, Preparation and Surface Activities of Cotelomers of Acrylic Acid and n-Octyl, 2-Ethylhexyl or 2-Phenylethyl Acrylate, Tomokazu Yoshimura; Koichi Hontake; Hideto Shosenji; Kunio Esumi, Cotelomers of acryric acid and n-octyl acrylate, 2-ethylhexyl acrylate or 2-phenylethyl acrylate with same carbon numbers (abbreviation by 2.1NoA-1.2AA, 1.9EhA-2.9AA and 1.6PeA-3.0AA, respectively 2.1,1.9 and 1.6 mean number of hydrophobic functions, 1.2, 2.9 and 3.0 mean number of carboxylate functions) were prepared by the radical cotelomerization in presence of 2-aminoethanethiol hydrochloride and examined for surface activity. Critical micelle concentrations (cmcs) of 2.1NoA-1.2AA and 1.9EhA-2.9AA were 1/16 and 1/5 of that of conventional surfactant of sodium n-octanoate. Surface tensions of aqueous solutions of 2.1NoA-1.2AA, 1.9EhA-2.9AA and 1.6PeA-3.0AA were 32.3, 27.3 and 41.1 mN m-1 at each cmc, respectively. 2.1NoA-1.2AA having straight alkyl chains and 1.9EhA-2.9AA having branched alkyl chains gave high foaming abilities in water as well as in hard water. 2.1NoA-1.2AA had high foam stability, while 1.9EhA-2.9AA showed poor stability. The highly stable oil-in-water type emulsions, which were brought about by shaking toluene with aqueous solutions of cotelomers, were formed by using 1.6PeA-3.0AA having aromatic nucleus. Interfacial tensions between aqueous solutions of 2.1NoA-1.2AA, 1.9EhA-2.9AA and 1.6PeA-3.0AA and toluene were 4, 8 and 1 mN m-1, respectively. © 2001, Japan Oil Chemists' Society. All rights reserved., 2001年, 50, 2, 103, 108, 研究論文（学術雑誌）, 10.5650/jos.50.103

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• 査読あり, 英語, COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, Preparation of gold nanoparticles using 2-vinylpyridine telomers possessing multi-hydrocarbon chains as stabilizer, K Esumi; A Kameo; A Suzuki; K Torigoe; T Yoshimura; Y Koide; H Shosenji, Gold nanoparticles have been prepared in water by reduction of HAuCl4 with NaBH4 in the presence of 2-vinylpyridine telomers. The telomers (nRm-2VPQ, n is the total number of chain; m is the main chain length) consist of multi-octyl side chains or multi-dodecyl side chains (2.1R(8)-2VPQ, 2.5R(12)-2VPQ, and 3.4R(12)-2VPQ). The particle size of gold decreases with increasing telomer concentration and stable gold nanoparticles are obtained above the critical micelle concentration of the telomer. The change in the particle size can be correlated with the structure of the telomer; when the alkyl chain length is longer and the total chain number is greater, the size becomes smaller. (C) 2001 Elsevier Science B.V. All rights reserved., 2001年01月, 176, 2-3, 233, 237, 研究論文（学術雑誌）
• 査読あり, 英語, 日本油化学会誌, Japan Oil Chemists' Society, Preparation and Surface Activity of Complexane-Type Surfactants Having Two and Three Alkyl Chains, 吉村倫一, 2及び3本のアルキル鎖を有するコンプレキサン系多鎖多親水基型界面活性剤 (2R_nida, 2R_nedda, 2R_ndtda, 3R_ndtda;nはアルキル鎖長を意味する) を各種アミン類と臭化物より合成し, それらの界面化学的性質について検討した。2, 3鎖型コンプレキサンの臨界ミセル濃度 (cmc) は, アルキル鎖長, 鎖数の増加及びスペーサーの長さの減少とともに低濃度側へ移行した。3R₈dtda, 3R₁₂dtdaのcmcは1鎖型界面活性剤2-アミノドデカン酸よりも2～3桁小さくなった。2, 3鎖型コンプレキサンのcmcにおける表面張力は, アルキル鎖長, 鎖数及びスペーサーの長さによって著しく異なり, 3R₈dtdaが24mNm^-1の最も優れた値を示した。3R_ndtdaの分子占面積は, R₁₂NAcの面積の3倍あるいは2R_nida, 2R_nedda, 2R_ndtdaの面積よりも小さくなった。2, 3鎖型コンプレキサン水溶液は, トルエンと振り混ぜることによりエマルションを形成した。2R₁₂idaは安定なwater-in-oil型エマルション, 鎖長10～12の2R_nedda, 2R_ndtda及び3R₈dtdaは安定なoil-in-water型エマルションを形成した。鎖長12のトルエン-コンプレキサン水溶液の界面張力は, いずれも1～2mNm^-1であった。各多鎖多親水基型コンプレキサンは, 親水性-疎水性バランス (HLB価) が約22のときに高い界面活性能を示し, 3R₈dtdaが気-液及び液-液界面において最も効率的な界面活性剤であった。, 2000年09月, 49, 9, 929-935, 935,973, 10.5650/jos1996.49.929

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• 査読あり, 英語, 日本油化学会誌, Japan Oil Chemists' Society, Preparation of Cotelomers of Acrylic Acid and n-Hexyl, 2-Ethylhexyl or n-Dodecyl Acrylate and Their Properties as Multi-Alkylated Surfactants, 吉村倫一, アクリル酸とアクリル酸アルキルコテロマーの多鎖型界面活性剤 (xR_mA-yAA, x, y及びmはそれぞれアルキル鎖の数, 親水基の数及びアルキル鎖長を意味する) を連鎖移動剤に2-アミノエタンチオール塩酸塩を用いて, アクリル酸とアクリル酸n-ヘキシル, 2-エチルヘキシル及びn-ドデシルのコテロメリゼーションにより合成し, 界面化学的性質について検討した。xR₆A-yAA, xR₈A-yAA及びxR₁₂A-yAA水溶液の表面張力は, それぞれ28～32, 27～30及び38～45mN m^-1であった。臨界ミセル濃度 (cmc) は, アルキル鎖数及び鎖長の増加に伴って減少した。300ppmのCa²⁺存在下では, 2.9R₆A-2.3AA, 2.8R₈A-2.5AA及び2.7R₁₂A-2.9AAは, それぞれ24, 28及び33mN m^-1の表面張力であった。短いアルキル鎖を有する2.9R₆A-2.3AAは高い泡沫安定性を示したが, 分岐鎖を有する2.8R₈A-2.5AAは低い安定性を示した。xR₆A-yAA, xR₈A-yAA及びxR₁₂A-yAA水溶液とトルエンとの界面張力は, それぞれ, 11～13, 8～12及び10～15mN m^-1であり, cmcは一般の界面活性剤ドデカン酸ナトリウムに比べて1/3～1/4となった。トルエンの乳化は, コテロマー水溶液と振り混ぜることによって形成し, 特に2～3本のアルキル鎖を有するコテロマーに高い安定な水中油滴型のエマルションが認められた。, 2000年08月, 49, 8, 801-808, 808,841, 10.5650/jos1996.49.801

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• 査読あり, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, Physicochemical properties of 2-vinylpyridine telomers possessing multihydrocarbon chains in aqueous solution and at the silica/aqueous solution interface, K Esumi; H Mizutani; K Shoji; M Miyazaki; K Torigoe; T Yoshimura; Y Koide; H Shosenji, Physicochemical properties of multialkylated surfactants of partially quaternized 2-vinylpyridine telomers having multihydro-carbon side chains (nRm-2VPQ: n, number of chains; m, alkyl chain length) in aqueous solutions were investigated. The critical micelle concentration (cmc) and surface tension at the cmc were 13 mu mol dm(-3) and 52 mNm(-1) for 2.1R(8)-2VPQ, 7.1 mu mol dm(-3) and 37 mNm(-1) for 2.5R(12)-2VPQ, and 4.7 mu mol dm(-3) and 40.0 mNm(-1) for 3.4R(12)-2VPQ, respectively. The aggregation numbers at the cmc determined by the light scattering method were 4 +/- 1 for 2.1R(8)-2VPQ, 45 +/- 10 for 2.5R(12)-2VPQ, and 11 +/- 1 for 3.4R(12)-2VPQ, Thus, the number of chains and the alkyl chain length of the telomers affected the micellar properties in aqueous solutions. At the interface of the silica/aqueous solution, the adsorbed amounts of the telomers increased sharply at their low concentrations and reached a plateau by forming a monolayer and a subsequent bilayer, Silica suspensions also showed a dispersion-flocculation-redispersion sequence with the telomer concentration, where the maximum sedimentation rate was influenced by the number of chains and the alkyl chain length of the telomers, (C) 1999 Academic Press., 1999年12月, 220, 1, 170, 173, 研究論文（学術雑誌）
• 査読あり, 英語, 日本油化学会誌, Japan Oil Chemists' Society, Surface Activities of Multi-Alkylated Surfactants of 2-Vinylpyridine Telomer with Polymerization Degree 4-6, 吉村倫一, 2～4本のアルキル鎖を持つ部分四級化2-ビニルピリジン系テロマーの多鎖多親水型界面活性剤 (xR_n-2VPQ, x及びR_nはそれぞれアルキル側鎖の数, アルキル鎖長を意味する) を, 重合度 (Pn) 4～6のテロマー塩酸塩から調製した。多鎖多親水型テロマーの界面化学的性質は, アルキル鎖長及び鎖数によってかなり影響を受けることがわかった。Pnca. 5の3.9R₈-2VP⁺Q及び3.4R₁₂-2VP⁺Q水溶液 (pH2) の臨界ミセル濃度での表面張力は, 28～29mN m^-1であった。界面活性能はテロマーの重合度によっても変化し, 3～4本のオクチル鎖あるいはドデシル鎖を持つ多鎖多親水型テロマー (Pnca. 5) は, 前報で報告したPn10～20の3～6本ドデシル側鎖型テロマーに比べ優れた界面活性能を示した。, 1999年11月, 48, 11, 1297-1302, 1302,1323, 10.5650/jos1996.48.1297

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• 査読あり, 日本語, 日本油化学会誌, Japan Oil Chemists' Society, 2-ビニルピリジン系テロマーを基本骨格とする3?6本ドデシル側鎖型界面活性剤の合成と界面化学的特性, 小出善文; 吉村倫一; 正泉寺秀人; 江角邦男, 多鎖多親水型界面活性剤として, 多数のドデシル側鎖をもった部分四級化2-及び4-ビニルピリジン系テロマー (nL-2VPQ, nL-4VPQ, nは側鎖の数を意味する) を重合度 (Pn) 5～20のテロマーから合成し, それらの界面化学的性質について検討した。ビニルピリジン系テロマーは, ドデカンチオール溶媒中で2-及び4-ビニルピリジンの重合により得られた。pH 2での表面張力は, Pn11の3.2～9.5L-2VP⁺Qが32～33mN・m^-1, Pn10の3.2L-4VP⁺Qが37mN・m^-1であった。これらの値はドデシル側鎖の数によって変化し, 臨界ミセル濃度 (cmc) も鎖数の増加に伴って低濃度側へ移行した。表面張力とcmcは, ピリジル基 (2-VP, 4-VP) 上でのドデシル側鎖の結合位置及び重合度によって変化した。Pn11のnL-2VP⁺Qは, nL-4VP⁺Q及びPn20のnL-2VP⁺Qより良好な表面張力低下能とcmcの低下を示した。トルエンはnL-2VP⁺Q, nL-4VP⁺Q水溶液と振り混ぜることによってエマルションになった。ドデシル側鎖の数はその乳化性に影響を及ぼし, Pn11のnL-2VP⁺Qは, Pn20のnL-2VP⁺QあるいはnL-4VP⁺Qより優れた乳化性を示した。最も優れた界面活性能は, Pn11の3.2～6.2L-2VP⁺Qに見られた。, 1999年02月, 48, 2, 123-130, 130, 10.5650/jos1996.48.123

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• その他, Colloids and Surfaces A: Physicochemical and Engineering Aspects, Surface adsorption and bulk properties of polyoxyethylene–polyoxypropylene random copolymer-type double-chained surfactants in quaternary-ammonium-salt-type amphiphilic gemini ionic liquids, Risa Kawai; Maiko Niki; Shiho Yada; Tomokazu Yoshimura, 2023年02月, 658, 130644, 130644, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2022.130644

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• その他, Colloids and Surfaces A: Physicochemical and Engineering Aspects, Linear- and star-type quaternary ammonium salt-based trimeric surfactants: Effect of structure on adsorption and aggregation properties, Tsukasa Morita; Shiho Yada; Tomokazu Yoshimura, 2023年01月, 656, 130364, 130364, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2022.130364

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• その他, Chemistry – A European Journal, Cover Feature: Fine Tunable, Redox Active Octapalladium Chains Supported by Linear Tetraphosphines, Leading to Dynamically 1D Self‐Assembled Coordination Polymers (Chem. Eur. J. 47/2021), Tomoaki Tanase; Kanako Nakamae; Haruka Miyano; Yasuyuki Ura; Yasutaka Kitagawa; Shiho Yada; Tomokazu Yoshimura; Takayuki Nakajima, 2021年08月19日, 27, 47, 12010, 12010, 研究論文（学術雑誌）, 10.1002/chem.202102416

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• その他, Heterocycles, Large-scale synthesis of thio-glucose-conjugated chlorin E6 for photodynamic therapy, Akihiro Nomoto; Hiroaki Yamaguchi; Masato Masuda; Keisuke Hyakumura; Shintaro Kodama; Tomohiro Osaki; Yoshiharu Okamoto; Mamoru Tanaka; Hiromi Kataoka; Atsushi Narumi; Tomokazu Yoshimura; Shigenobu Yano; Akiya Ogawa, Chlorin e6 is a heterocycle exhibiting spectral absorption in the 600-700 nm wavelength range used for photodynamic therapy (PDT). Herein, a sugar-conjugated chlorin e6 derivative was synthesized on a large scale. An alkyl spacer was fabricated by controlling the alkoxylation conditions between the thio-sugar and chlorin e6 and thio-glucose-conjugated chlorin e6 was successfully synthesized., 2021年, 103, 2, 研究論文（学術雑誌）, 10.3987/COM-20-S(K)73

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• その他, Quantum Beam Science, Microscopic Depictions of Vanishing Shampoo Foam Examined by Time-of-Flight Small-Angle Neutron Scattering, Satoshi Koizumi; Yohei Noda; Takumi Inada; Tomoki Maeda; Shiho Yada; Tomokazu Yoshimura; Hiroshi Shimosegawa; Hiroya Fujita; Munehiro Yamada; Yukako Matsue, A novel surfactant of N–dodecanoyl–N–(2-hydroxyethyl)–β–alanine (coded as C12–EtOH–βAla) was synthesized by modifying the methyl group of N–dodecanoyl–N–methyl–β–alanine (coded as C12–Me–βAla). Amino-acid-type surfactants (C12–EtOH–βAla and C12–Me–βAla) are more healthy and environmentally friendly compared to sodium dodecyl sulfate (SDS). To investigate the microstructures of these new surfactants, we employed a method of time-of-flight small-angle neutron scattering (TOF SANS) at a pulsed neutron source, Tokai Japan (J–PARC). The advances in TOF SANS enable simultaneous multiscale observations without changing the detector positions, which is usually necessary for SANS at the reactor or small-angle X-ray scattering. We performed in situ and real-time observations of microstructures of collapsing shampoo foam covering over a wide range of length scales from 100 to 0.1 nm. After starting an air pump, we obtained time-resolved SANS from smaller wave number, small-angle scattering attributed to (1) a single bimolecular layer with a disk shape, (2) micelles in a bimolecular layer, and (3) incoherent scattering due to the hydrogen atoms of surfactants. The micelle in the foam film was the same size as the micelle found in the solution before foaming. The film thickness (~27 nm) was stable for a long time (<3600 s), and we simultaneously found a Newton black film of 6 nm thickness at a long time limit (~1000 s). The incoherent scattering obtained with different contrasts using protonated and deuterated water was crucial to determining the water content in the foam film, which was about 10~5 wt%., 2023年01月29日, 7, 1, 4, 4, 研究論文（学術雑誌）, 10.3390/qubs7010004

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• 査読あり, 日本語, 材料表面, 四級アンモニウム塩系両親媒性イオン液体の界面吸着と層構造, 河合里紗; 矢田詩歩; 吉村倫一, 2022年08月, 7, 3, 92, 102, 研究論文（学術雑誌）
• その他, Colloids and Surfaces A: Physicochemical and Engineering Aspects, Adsorption dynamics of quaternary-ammonium-salt–based gemini and trimeric surfactants with different spacer structures at air/water interface, Tsukasa Morita; Shiho Yada; Tomokazu Yoshimura, 2023年05月, 671, 131589, 131589, 研究論文（学術雑誌）, 10.1016/j.colsurfa.2023.131589

  DOI URL
• その他, Physical Chemistry Chemical Physics, Catalytic activity of gold nanoparticles protected by quaternary ammonium salt-based gemini surfactants with different spacer structures, Tsukasa Morita; Shiho Yada; Tomokazu Yoshimura, The structure and catalytic activities of gold nanoparticles were affected by the spacer structure., 2023年, 25, 24, 16288, 16293, 研究論文（学術雑誌）, 10.1039/d3cp01116j

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• その他, Journal of Oleo Science, Micelle Formation of Dodecanoic Acid with Alkali Metal Counterions, Keisuke Matsuoka; Aiko Sato; Yukino Ogawa; Kana Okazaki; Shiho Yada; Tomokazu Yoshimura, 2023年, 72, 9, 831, 837, 研究論文（学術雑誌）, 10.5650/jos.ess23086

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• 査読あり, 英語, Langmuir, Stability and Structural Analysis using Small-Angle Neutron Scattering for Foam of Homogeneous Polyoxyethylene type Nonionic Surfactant with Multi–Branched chains, Shiho Yada; Mizuho Kuroda; Masashi Ohno; Toshinari Koda; Tomokazu Yoshimura, 2023年10月31日, 39, 43, 15355, 15361, 研究論文（学術雑誌）, 10.1021/acs.langmuir.3c02424

  DOI URL

MISC

• その他, Proceedings of the 3rd J-PARC Symposium (J-PARC2019), Journal of the Physical Society of Japan, Rheo-SANS Study on Shear Thinning Behavior of Cationic Gemini Surfactant (12–2–12) in Salt-free Solution, Hiroki Iwase; Risa Kawai; Tomokazu Yoshimura; Shin-ichi Takata, 2021年03月26日, 10.7566/jpscp.33.011078

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• 査読あり, 英語, JPS Conf. Proc., Structural Study of a Gold Nanoparticle/Sugar-type Surfactant Complex by SANS, SAXS, TEM, and EXAFS Techniques, K. Akutsu; H. Iwase; Y. Nakatani; T. Yoshimura, 2015年, 8, 033011, 10.7566/JPSCP.8.033011

  DOI URL
• 査読あり, その他, JPS Conf. Proc., SANS and SAXS studies on the aggregates properties of a gemini-type amphiphilic dendrimer in solution, H. Iwase; N. K. Kawano; K. Akutsu; T. Yoshimura, 2015年, 8, 033012
• 査読無し, 日本語, コンバーテック, 次世代クローズド水系洗浄システム, 仲野真一; 山本健; 矢田詩歩; 吉村倫一; 林啓太; 中村秀美, 2014年07月, 42, 7, 109-111
• 査読無し, 日本語, コンバーテック, 次世代洗浄システムによるデバイス製造工程のパラダイムシフト, 仲野真一; 山本健; 長谷部伸治; 矢田詩歩; 吉村倫一, 2014年05月, 42, 5, 71-73
• 査読無し, 日本語, オレオサイエンス, 公益社団法人 日本油化学会, 特異な構造を有する新規界面活性剤の合成と物性に関する研究（総説）, 吉村倫一, 界面活性剤は界面において様々な機能を発揮する物質であり，その化学構造と機能との関係は学術的にも実用的にも非常に重要である。本稿では，表面におけるRf基の配向を制御して緊密にパッキングすることを目標として，「Rf基と導入点の間にメチレン鎖を挿入したセミフルオロアルキル基（Semi-Rf）を多鎖型で有する」を新たなコンセプトとして提起するとともに，両端にRf基を有する含フッ素オリゴマー型界面材料，Semi-Rf基を二鎖型で側鎖に導入したポリマー型表面改質剤，Semi-Rf基を二鎖型で有するGemini型界面活性剤の開発に関する筆者の研究成果を概説した。さらに，環境適応型の界面活性剤として，コリノミコール酸，Gemini型界面活性剤の開発，ならびに酒石酸型Geminiやコハク酸型Geminiにおける分子の立体化学と界面機能との関係についても述べた。, 2013年12月, 13, 12, 587-597, 585, 10.5650/oleoscience.13.573

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• 査読無し, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, ACADEMIC PRESS INC ELSEVIER SCIENCE, Aggregation properties of supralong-chain surfactants with double or triple quaternary ammonium head groups, Keisuke Matsuoka; Nagisa Chiba; Tomokazu Yoshimura, Double or triple quaternary ammonium head groups were designed to improve the solubility of supralong alkyl chain surfactants. In the surfactant head group, quaternary ammonium groups are connected by an ethylene spacer. Micellar shapes of divalent surfactants [CH2n+1N+(CH3)(2)-(CH2)(2)-N(CH3)(3) 2Br(-): C-n-2Am (n = 18, 20, and 22)] and trivalent surfactants [CnH2n+1N+(CH3)(2)-(CH2)(2)-N+(CH3)(2)-(CH2)(2)-N+(CH3)(3) 3Br(-): C-n-3Am (n = 18, 20, and 22)] were studied in aqueous solutions by means of dynamic light scattering (DLS) and transmission electron microscopy (TEM). Changes in the surfactant concentration have a small influence on the apparent hydrodynamic radii (r(h)) of the molecular aggregates in both surfactant series. Average values of r(h) of aggregates are 60-90 nm for C-n-2Am (n= 18, 20, and 22) and 2-40 nm for C-n-3Am (n = 18, 20, and 22). TEM micrographs showed that aggregates of C-n-2Am (n = 18, 20, and 22) typically formed rod-like micelles. In contrast, trivalent surfactants of C-n-3Am (n = 18, 20, and 22) formed spherical (C-18-3Am) or ellipsoidal micelles (C-20-3Am and C-22-3Am). Moreover, the degree of micellar counterion binding for these surfactants was determined by using a bromide ion-selective electrode, which indicated relatively high values (0.8-0.9) for C-n-2Am (n = 18, 20, and 22) and more common values (0.5-0.8) for C-n-3Am (n = 18, 20, and 22). The size of the aggregates is closely related to the degree of counterion binding. (C) 2012 Elsevier Inc. All rights reserved., 2012年08月, 379, 1, 72, 77, 10.1016/j.jcis.2012.04.043

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• 査読無し, 日本語, 光散乱ジャーナル LSアドバンス, ジェミニ型界面活性剤の水溶液中でのミセル構造, 吉村倫一, 2011年11月, 10, 2-8
• 査読無し, 日本語, オレオサイエンス, フッ素系ジェミニ型界面活性剤（総説）, 吉村倫一, 2011年09月, 11, 9, 319-326
• 査読無し, 日本語, フレグランス ジャーナル, フレグランスジャーナル社, 環境に適した新規糖型界面活性剤の開発（特集）, 吉村倫一, 2009年08月, 37, 8, 26-32, 32

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• 査読無し, 日本語, 日本化学会コロイドおよび界面化学部会ニュースレター, 特異な構造を有する次世代界面活性剤の分子設計（Interface）, 吉村倫一, 2008年03月, 33, 1, 7-12
• 査読無し, 英語, Colloids Surf., A, Synthesis and Surface-Active Properties of Sulfobetaine-Type Zwitterionic Gemini Surfactants, 吉村倫一, 2006年02月, 273, 208-212
• 査読無し, 英語, JOURNAL OF COLLOID AND INTERFACE SCIENCE, ACADEMIC PRESS INC ELSEVIER SCIENCE, Voltammetric study of sodium hypochlorite using dendrimer-stabilized gold nanoparticles, T Endo; T Yoshimura; K Esumi, Electrochemical activity of dendrimer-stabilized gold nanoparticles on a glassy carbon electrode (GCE) was studied by means of cyclic voltammetry of sodium hypochlorite. Dendrimer-stabilized gold nanoparticles were deposited onto a glassy carbon surface by electrophoresis and the deposition was observed by transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Both anodic and cathodic peak currents were found to increase after the deposition of dendrimer-stabilized gold nanoparticles. In the case of dendrimers deposited onto the GCE surface, the magnitude of the current was smaller than for dendrimer-stabilized-gold-nanoparticle-modified GCE. This indicates the enhancement in the rate of electrolysis due to gold nanoparticles. (C) 2003 Elsevier Inc. All rights reserved., 2004年01月, 269, 2, 364, 369, 10.1016/S0021-9797(03)00674-X

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• 査読無し, 英語, Studies in Surface Science and Catalysis, Preparation and Surface-Active Properties of Cotelomer Type Surfactants of Alkyl Acrylate and Acrylic Acid, 吉村倫一, 2001年, 132, 145-148

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• 化学便覧 基礎編 改訂6版, 丸善, 16.4.2「ミセル」担当, 2021年01月, その他, その他
• 界面活性剤の選び方、使い方 事例集（第2章第3節「ユニークな構造のポリオキシエチレン系非イオン界面活性剤の開発」担当（矢田詩歩，吉村倫一））, 技術情報協会, 吉村倫一; 名執筆者, 分担, 2019年04月, pp.**-**, 日本語, 査読無し, その他
• ─化粧品開発のための最新の美容皮膚科学理論と具現化するための最新の処方技術─ 最新・化粧品開発のための美容理論、処方/製剤、機能評価の実際（第32章「ジェミニ型界面活性剤の創製～アミノ酸・糖・ポリオキシエチレンを用いて」担当（矢田詩歩，吉村倫一））, 技術教育出版, 吉村倫一; 名執筆者, 分担, 2018年07月, pp.322-333, 日本語, 査読無し, その他
• 泡の生成メカニズムと応用展開, シーエムシー出版, 吉村倫一; 名執筆者, 分担, 2017年04月, pp.101-110, 日本語, 査読無し, その他
• 界面活性剤の最新研究・素材開発と活用技術, シーエムシー出版, 吉村倫一; 名執筆者, 分担, 2016年08月, pp.53-64, 日本語, 査読無し, その他
• エマルションの特性評価と新製品開発、品質管理への活用－吸着挙動の解析、界面張力の測定、構造の解析、安定性の評価－（第2章4節「界面活性剤の性能評価法」担当）, 技術情報協会, 吉村倫一; 名執筆者, 分担, 2014年10月, pp.53-60, 日本語, 査読無し, その他
• 油脂・脂質・界面活性剤データブック, 丸善, 吉村倫一, 分担, 2012年12月, 日本語, 査読無し, その他
• 改訂第2版 界面と界面活性剤－基礎から応用まで－（第3章7節「ポリマー界面活性剤」担当）, 日本油化学会, 吉村倫一, 分担, 2009年03月, pp.83-88, 日本語, 査読無し, その他
• 油化学辞典 脂質・界面活性剤 第二版, 丸善, 吉村倫一; 阿部正彦; 名編集委員, 分担, 2006年05月, 日本語, 査読無し, その他
• 界面と界面活性剤－基礎から応用まで－（第2章7節「ポリマー界面活性剤」担当）, 日本油化学会, 吉村倫一, 分担, 2005年04月, pp.75-79, 日本語, 査読無し, その他
• 油化学辞典 脂質・界面活性剤, 丸善, 吉村倫一; 阿部正彦; 名編集委員, 分担, 2004年03月, 日本語, 査読無し, その他
• Structure-Performance Relationships in Surfactants 2nd ed (Chap.9"Surface-Active Properties of Telomer-Type Surfactants Having Several Hydrocarbon Chains"担当), Marcel Dekker, 吉村倫一, 分担, 2003年, pp.399-432, 英語, 査読無し, その他
• NMRによる有機材料分析とその試料前処理、データ解釈, 技術情報協会, 第5章3節「NMR法による界面活性剤の分析」担当, 2021年09月, その他, その他
• エマルションの安定化のための新しい調製技術と評価, 技術情報協会, 技術情報協会, 第２章３節「界面吸着とミセル形成」, 2022年10月, 714p, 日本語, その他, 9784861049002

  CiNii Books URL
• 洗浄の事典, 朝倉書店, 大矢, 勝; 天田, 徹; 荒牧, 賢治; 北村, 裕夫; 蓼沼, 裕彦; 中村, 一穂; 松宮, 正彦; 山田, 勲, 3-11「2鎖型・ジェミニ型・トリメリック型」, 2022年10月, xiv, 535, 9p, 図版 [4] p, 日本語, その他, 9784254252736

  CiNii Books URL
• 泡の生成・消泡の基礎と産業利用, シーエムシー出版, 吉村 倫一, 第1章「泡の構造と性質」; 第2章「泡に必要な界面活性剤の基礎」; 第4章「起泡力と泡沫安定性に及ぼす因子」; 第5章-2「ヒドロキシ基含有アミノ酸系界面活性剤」, 2022年09月, v, 300p, 日本語, その他, 9784781316772

  CiNii Books URL

講演・口頭発表等

• 吉村倫一, 国内, R&Dセミナー（株式会社R&D支援センター主催）, 乳化・可溶化の基礎知識と最新のエマルションの設計技術～乳化剤の種類・性質 / 乳化・可溶化の調製、評価方法、安定化技術～, 公開講演，セミナー，チュートリアル，講習，講義等, 日本語

Works（作品等）

• X線小角散乱を用いた両親媒性化合物が形成する会合体の会合体特性に関する研究（企業）, 2016年04月
• 界面活性剤の物性に関する研究（企業）, 2015年07月
• 新規非イオン性界面活性剤の開発（企業）, 2015年04月
• 新規界面活性剤の開発（企業）, 2015年04月
• 新規非イオン性界面活性剤の物性に関する研究（企業）, 2015年04月
• アダマンタンを用いた両親媒性化合物の開発と性能評価（企業）, 2011年04月, 2015年03月
• 界面活性剤を用いた新規洗浄液の開発（企業）, 2013年, 2015年
• 糖含有新規ジェミニ型界面活性剤の開発（企業）, 2014年04月
• 界面活性剤ミセルの可溶化に関する研究, 2013年04月
• 界面活性剤水溶液の物性と会合体形成に関する研究, 2006年09月, 2013年03月
• ジェミニ型陽イオン界面活性剤の開発（企業）, 2013年
• 乳酸菌発酵米を用いた乳化のメカニズム（企業）, 2012年04月
• X線小角散乱SAXSを用いた分子集合体のナノ構造解析, 2010年
• 界面活性剤が形成する会合体の極低温透過型電子顕微鏡によるナノ構造解析, 2009年10月
• カルボン酸金属塩の物性および応用に関する研究, 2001年, 2008年
• 中性子小角散乱を用いた界面活性剤ミセルの構造解析に関する研究, 2003年, 2005年
• 透過型電子顕微鏡を用いた界面活性剤ミセルの構造解析に関する研究, 2004年, 2004年

受賞

• 20th J. Oleo Sci. Editor's Award, 公益社団法人日本油化学会, 吉村倫一, 2017年05月
• 平成24年度日本油化学会進歩賞, 公益社団法人日本油化学会, 吉村倫一, 2013年04月
• 平成18年度色材協会賞（論文賞）, 社団法人色材協会, 2006年09月
• 平成15年度色材協会賞（論文賞）, 社団法人色材協会, 2003年

産業財産権

• 特許権, アルキル糖ーアミノ酸の結合体, 吉村倫一, 羽田容介、澤木茂、澤木茂豊、吉村倫一, 特願20180038814, 2018年03月05日, 201809, 2018年09月20日
• 特許権, カチオン性ジェミニ型界面活性剤, 吉村倫一, 瀬底祐介、吉村倫一, 特願20160171703, 2016年09月02日, 201803, 2018年03月08日
• 特許権, カチオン性ジェミニ型界面活性剤, 吉村倫一, 瀬底祐介、吉村倫一, 特願20160171702, 2016年09月02日, 201803, 2018年03月08日
• 特許権, ジェミニ型界面活性剤, 吉村倫一, 徳本勝美、吉村倫一, 特願20160154902, 2016年08月05日, 201703, 2017年03月16日
• 特許権, ジェミニ型界面活性剤, 吉村倫一, 若林保武，吉村倫一, 特願2014-047268, 2014年03月11日, 201509, 2015年09月28日
• 特許権, 貴金属コロイド内包ラメラ構造体、その分散液及びこれを含む化粧品並びにその分散液の製造方法, 吉村倫一, 高橋康之 外６名, 特許出願2006-80734, 2006年03月23日, 200710, 2007年10月04日
• 特許権, 低沸点有機化合物の固形化方法，その取り扱い方法及び固形状集合体からの低沸点有機化合物の再生方法, 吉村倫一, 坂口豁，吉村倫一，他１名, 2001, 2001年

共同研究・競争的資金等の研究課題

• 2021年04月01日, 2022年03月31日, 研究代表者, 日油㈱・㈱アルビオン共同研究
• 2008年, 金属ナノ粒子の調製と物性に関する研究, 0, 0, 0, 競争的資金
• 2005年, 環境適合型界面活性剤を用いたエマルションの物性に関する研究, 0, 0, 0, 競争的資金
• 2005年, Study on Liquid/Liquid Interface and Emulsion, 0, 0, 0, 競争的資金
• 2003年, X線・中性子小角散乱、低温透過型電子顕微鏡を用いた分子集合体のナノ構造解析に関する研究, 0, 0, 0, 競争的資金, rm:published_papers

  対象リソースIRI
• 2003年, Study on Self-Organization of Surfactant with Special Structure, 0, 0, 0, 競争的資金
• 2001年, 界面活性剤の水溶液物性に関する研究, 0, 0, 0, 競争的資金
• 2001年, Study on Solution Properties of Surfactant, 0, 0, 0, 競争的資金
• 1998年, 高性能・高機能化を目指した新規界面活性剤および両親媒性高分子の開発, 0, 0, 0, 競争的資金
• 1998年, Design and Synthesis of Novel Surfactants and Polymers with High Functions, 0, 0, 0, 競争的資金
• 金属ナノ粒子の開発, 0, 0, 0, 競争的資金
• エマルションの調製と物性評価, 0, 0, 0, 競争的資金
• 小角散乱を用いた分子集合体のナノ構造解析, 0, 0, 0, 競争的資金
• 次世代型新規界面活性剤の開発と性能評価（ジェミニ型、オリゴマー型、両親媒性高分子型、糖鎖型、フッ化炭素系など）, 0, 0, 0, 競争的資金
• 2021年04月01日, 2022年03月31日, 研究代表者, ワミレスコスメティックス㈱共同研究
• 2021年06月01日, 2022年05月31日, 研究代表者, ㈱アルビオン共同研究
• 2021年11月01日, 2022年05月31日, 研究代表者, ㈱ニイタカ共同研究
• 2021年04月01日, 2022年03月31日, 研究代表者, ㈱日本触媒共同研究
• 2021年04月01日, 2022年03月31日, 研究代表者, 阪本薬品工業㈱共同研究
• 2021年04月01日, 2022年03月31日, 研究代表者, 日産化学㈱共同研究
• 2021年04月01日, 2022年03月31日, 研究代表者, 日油㈱共同研究

Ⅲ．社会連携活動実績

１．公的団体の委員等（審議会、国家試験委員、他大学評価委員，科研費審査委員等）

• 日本化学会, 近畿支部幹事、代表正会員, 学協会
• 日本化学会コロイドおよび界面化学部会, 関西支部委員, 学協会
• 日本化学会コロイドおよび界面化学部会, 広報委員会委員, 学協会
• 日本化学会コロイドおよび界面化学部会, 討論会委員会委員, 学協会
• 日本化学会コロイドおよび界面化学部会, 編集委員会委員長, 学協会
• 日本油化学会, 若手の会委員長, 学協会
• 日本化学会コロイドおよび界面化学部会, 編集委員会副委員長, 学協会
• 日本化学会コロイドおよび界面化学部会, 編集委員会委員, 学協会
• 日本油化学会, 関西支部幹事, 学協会
• 日本化学会コロイドおよび界面化学部会, 役員会幹事, 学協会
• 日本化学会コロイドおよび界面化学部会, 副支部長
• 日本化学会コロイドおよび界面化学部会 関西支部, 支部長, 2022年04月, 2024年03月, 学協会
• 日本油化学会 界面科学部会, 部会長, 2021年04月, 2023年03月, 学協会
• 日本化学会コロイドおよび界面化学部会, 広報委員会委員
• 日本化学会コロイドおよび界面化学部会, 討論会委員会委員
• 日本油化学会, 関西支部幹事
• 日本化学会コロイドおよび界面化学部会, 役員会幹事
• 日本油化学会 関西支部, 常任幹事長, 2023年04月, 2025年03月, 学協会
• 日本油化学会 界面科学部会, 副部会長, 2023年04月, 2024年03月, 学協会
• 日本油化学会 関西支部, 常任副幹事長, 2021年04月, 2023年03月, 学協会