研究者詳細 - 大久保　貴広

論文 - 大久保　貴広

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Adsorption and micellization behavior of novel gluconamide-type gemini surfactants 査読

Kenichi Sakai, Shin Umezawa, Mamoru Tamura, Yuichiro Takamatsu, Koji Tsuchiya, Kanjiro Torigoe, Takahiro Ohkubo, Tomokazu Yoshimura, Kunio Esumi, Hideki Sakai, Masahiko Abe

JOURNAL OF COLLOID AND INTERFACE SCIENCE 318 ( 2 ) 440 - 448 2008年2月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ACADEMIC PRESS INC ELSEVIER SCIENCE

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.

DOI： 10.1016/j.jcis.2007.10.039

カチオン／アニオン界面活性剤混合系を利用したチタニア／界面活性剤複合粒子の調製とナノ構造制御査読

酒井秀樹, 河野浩輝, 萩原英輝, 小倉卓, 柴田裕史, 酒井健一, 大久保貴広, 阿部正彦

J. Jpn. Soc. Colour Mater. 81 ( 9 ) 325 - 330 2008年

記述言語：日本語出版者・発行元：Japan Society of Colour Material

カチオン界面活性剤とアニオン界面活性剤の混合水溶液中で形成されるナノサイズの分子集合体の存在下で酸化硫酸チタンの加水分解・重縮合反応を行うことにより, ナノサイズの規則的構造を有するチタニア／界面活性剤複合粒子を調製した。また, 界面活性剤の混合比を変化させることにより規則構造の間隔および形態制御を試みた。カチオン界面活性剤にセチルトリメチルアンモニウムブロミド (CTAB), アニオン界面活性剤にソディウムオクチルサルフェイト (SOS) を用いたところ, SOSの混合比が小さいときにはヘキサゴナル型の規則構造を有する粒子が得られ, 規則構造の周期はSOS混合比の増大とともに増加した。一方, ある混合比を超えるとラメラ型の規則構造へと変化し, 規則構造の周期は逆に減少することがわかった。また, アニオン界面活性剤としてSOSの替わりにソディウムドデシルサルフェイト (SDS) またはソディウムオクタノエート (SO) を用いた際にも同様の傾向が観測されたが, 規則構造周期の絶対値ならびに相変化組成は界面活性剤種により変化した。以上の結果より, カチオン／アニオン界面活性剤混合比の変化により規則的構造の周期および形態をオングストロームオーダーで精密に制御できることがわかった。

DOI： 10.4011/shikizai.81.325

その他リンク： https://jlc.jst.go.jp/DN/JALC/00319065301?from=CiNii

Photo-isomerization of spiropyran-modified cationic surfactants 査読

Hideki Sakai, Hiroatsu Ebana, Kenichi Sakai, Koji Tsuchiya, Takahiro Ohkubo, Masahiko Abe

JOURNAL OF COLLOID AND INTERFACE SCIENCE 316 ( 2 ) 1027 - 1030 2007年12月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ACADEMIC PRESS INC ELSEVIER SCIENCE

Photo-induced isomerization of a newly synthesized surfactant,1'(6-trimethylammoniododecyl)-3',3'-dimethyl-6-nitrospiro-(2H-1-benzopyran-2,2'-indoline) bromide (SP-Me-12), has been characterized on the basis of the UV-vis absorption spectra and the surface tension data. Visible light (lambda > 420 nm) incident on the aqueous solution of SP-Me-12 results in the isomerization from the merocyanine (MC) form to the spiropyran (SP) form; this structural change was confirmed by a complete disappearance of a characteristic absorption peak of the MC form. When the surfactant solution is stored in the dark, the isomerized SP form reverts to the original MC form, however, the reverse isomerization rate is observed to be considerably slower than that seen for visible light irradiation (from the MC form to the SP form). A reversible change in the surface tension of the aqueous surfactant solution is observed for the photo-induced isomerization: the surface tension measured below the critical aggregation concentration decreases as a result of the visible light irradiation and it is gradually reversed to the original level during the equilibration in the dark. (C) 2007 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jcis.2007.08.042

Phase behavior of mixed solution of a glycerin-modified cationic surfactant and an anionic surfactant 査読

Koji Tsuchiya, Jun Ishikake, Tae Seong Kim, Takahiro Ohkubo, Hideki Sakai, Masahiko Abe

JOURNAL OF COLLOID AND INTERFACE SCIENCE 312 ( 1 ) 139 - 145 2007年8月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ACADEMIC PRESS INC ELSEVIER SCIENCE

The phase behavior of mixed solution of newly synthesized monoglycerylcetyldimethylammonium chloride (MGCA) and sodium octyl sulfate (SOS) in water was investigated by cryo-transmission electron microscopy (cryo-TEM), dynamic light scattering (DLS), differential scanning calorimetry (DSC), and fluorescence polarizing for evaluation of the microviscosity of bilayers. No precipitate was observed in the mixed solution except at concentrations below 20 mM over all mixing ratios, and stable vesicles were formed in a considerably wide range of mixing ratio, even at the equimolar ratio. Vesicles formed in aqueous 1/1 MGCA/SOS mixture were found to exhibit no phase transition, and fluorescence polarizing measurements showed that the vesicle bilayers have a high fluidity. This flexibility allows the bilayers to have a spontaneous curvature, and thus vesicles rather than flat lamellae can be stabilized in the mixture even at the equimolar ratio. In addition, because the glycerin group of MGCA interacts strongly with water, the hydration repulsion contributes to prevent the bilayers consisting of MGCA and SOS from adhering and floccuiating even though the charge neutralization between MGCA and SOS occurs at the equimolar ratio. (c) 2006 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jcis.2006.07.075

Synthesis of highly-ordered mesoporous silica particles using mixed cationic and anionic surfactants as templates 査読

Takahiro Ohkubo, Taku Ogura, Hideki Sakai, Masahiko Abe

JOURNAL OF COLLOID AND INTERFACE SCIENCE 312 ( 1 ) 42 - 46 2007年8月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ACADEMIC PRESS INC ELSEVIER SCIENCE

We applied a molecular assembly formed in an aqueous surfactant mixture of cationic cetyltrimethylammonium bromide (CTAB) and anionic sodium octylsulfate (SOS) as templates of mesoporous silica materials. The hexagonal pore size can be controlled between 3.22 and 3.66 nm with the mixed surfactant system. In addition, we could observe the lamellar structure of the mixed surfactants with precursor molecules, which strongly shows the possibility of precise control of both the pore size and the structure of pores by changing the mixing ratio of surfactants. Moreover, use of the cationic surfactant having longer hydrophobic chain like stearyltrimethyl ammonium bromide (STAB) caused the increase in dloo space and shifted the point of phase transition from hexagonal phase to lamellar phase to lower concentration of SOS. (c) 2007 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jcis.2007.02.043

Preparation of petaloid microspheres of basic magnesium carbonate 査読

Takahiro Ohkubo, Sei Suzuki, Kohei Mitsuhashi, Taku Ogura, Shinichi Iwanaga, Hideki Sakai, Masumi Koishi, Masahiko Abe

LANGMUIR 23 ( 11 ) 5872 - 5874 2007年5月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

The synthesis of basic magnesium carbonate was examined under ultrasonic irradiation and was performed by the soda ash method using magnesium sulfate and sodium carbonate as starting materials. The particulate product was evaluated using SEM observations. Ultrasonic irradiation in the preparation of basic magnesium carbonate was found to give fine petaloid microspheres of about 3 mu m in primary particle size.

DOI： 10.1021/la7002782

RBM band shift-evidenced dispersion mechanism of single-wall carbon nanotube bundles with NaDDBS 査読

Shigenori Utsumi, Mamiko Kanamaru, Hiroaki Honda, Hirofumi Kanoh, Hideki Tanaka, Takahiro Ohkubo, Hideki Sakai, Masahiko Abe, Katsumi Kaneko

JOURNAL OF COLLOID AND INTERFACE SCIENCE 308 ( 1 ) 276 - 284 2007年4月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ACADEMIC PRESS INC ELSEVIER SCIENCE

The dispersion process of single-wall carbon nanotube (SWNT) by using sodium dodecylbenzene sulfortate (NaDDBS) was studied by means of surface tension measurements, ultraviolet-visible (UV-Vis) spectroscopy, scanning electron microscopy (SEM), and transmission electron spectroscopy (TEM). The critical micelle concentration (CMC) and the concentration where the surface tension begins to drop increase by the presence of SWNT. The isotherm of NaDDBS amount adsorbed on SWNT shows the plateau region at 0.2-6 mM and the saturated region above 40 mM. The external surface of SWNT bundle is fully covered with adsorbed NaDDBS at the plateau region, showing that SWNTs can be dispersed with the bundle form. On the other hand, SWNTs are dispersed in individual tubes at the saturated region, where the adsorption amount corresponds to coating of individual tube surfaces with NaDDBS. This dispersion state was confirmed by SEM and TEM observations. The effect of the dispersion state of SWNTs on radial breathing mode in Raman spectrum gave inherent peak shifts, being the in situ evidences on the g step-wise dispersion mechanism of the SWNT bundle to the individual tubes. (c) 2006 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jcis.2006.12.041

Adsorption and aggregation properties of amino acid-based N-alkyl cysteine monomeric and N,N '-dialkyl cystine gemini surfactants 査読

Tomokazu Yoshimura, Ayako Sakato, Koji Tsuchiya, Takahiro Ohkubo, Hideki Sakai, Masahiko Abe, Kunio Esumi

JOURNAL OF COLLOID AND INTERFACE SCIENCE 308 ( 2 ) 466 - 473 2007年4月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ACADEMIC PRESS INC ELSEVIER SCIENCE

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.

DOI： 10.1016/j.jcis.2006.11.038

Cationic surfactant changes the morphology of DNA molecules 査読

Hisanori Nakanishi, Koji Tsuchiya, Takahiro Okubo, Hideki Sakai, Masahiko Abe

LANGMUIR 23 ( 2 ) 345 - 347 2007年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

The effect of cetyltrimethylammonium bromide (CTAB), a cationic surfactant, was investigated on the aggregated form of DNA molecules in water at a given temperature. CTAB caused changes in the aggregated form of DNA molecules from loosely packed spherical to rodlike through toroidal one with increasing concentration below the critical micelle concentration (CMC). The change was suggested to arise from the ion complex formation between CTAB and DNA molecules due to the electrostatic interaction, thereby reducing the surface charge and solubility in water of the latter.

DOI： 10.1021/la051443p

その他リンク： http://orcid.org/0000-0001-5907-3683

Synthesis and properties of a microtube photocatalyst with photoactive inner surface and inert outer surface 査読

Kohei Mitsuhashi, Naoki Tagami, Katsuyuki Tanabe, Sei Suzuki, Shinichi Iwanaga, Takahiro Ohkubo, Hideki Sakai, Masumi Koishi, Masahiko Abe

JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY 185 ( 2-3 ) 133 - 139 2007年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCIENCE SA

Synthesis of a photocatalyst with a novel particle form, its photoactivity, and the degradation of polyvinyl alcohol containing the photocatalyst were studied in detail. A microtube photocatalyst with titanium dioxide particles supported on the inner surface of the microtube was synthesized by adding fine titanium dioxide particles in the formation process of basic magnesium carbonate microtube. The photoactivity of the microtube photocatalyst was confirmed from the decomposition of 2-propanol under blacklight irradiation. Moreover, the microtube photocatalyst was found to cause no degradation of polyvinyl alcohol, whereas, it decomposed 2-propanol with its photoactivity when impregnated in a polyvinyl alcohol foam. This fact was considered to be derived from the unique structure of the microtube photocatalyst, which has a photoactive inner surface with titanium dioxide and an inert outer surface of basic magnesium carbonate. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jphotochem.2006.04.047

Preparation of tiny biodegradable capsules using electrocapillary emulsification 査読

Masahiko Abe, Ai Nakayama, Tamotsu Kondo, Hiroshi Morishita, Koji Tsuchiya, Shigenori Utsumi, Takahiro Ohkubo, Hideki Sakai

JOURNAL OF MICROENCAPSULATION 24 ( 8 ) 777 - 786 2007年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：TAYLOR & FRANCIS LTD

Conditions for preparing tiny biodegradable capsules were examined using electrocapillary emulsification that allows one to prepare monodisperse emulsions with ease by applying a DC potential between oil and water phases without mechanical agitation. The results obtained showed that a 1:4 mixture of polysorbate 80 (TO-10), a hydrophilic non-ionic surfactant, and sorbitan monooleate (SO-10), an oleophilic surfactant, is appropriate as the surfactant to be added to oil phase, cyclohexane is acceptable as the oil phase and 1000 V is optimum as the DC potential to be applied. The capsules prepared had sizes ranging from 100 - 300 nm and a surface roughness of similar to 10nm and degraded in model intestinal juice more easily and rapidly than in model gastric juice. In addition, the capsules containing lactoferrin, an anti-carcinogenic protein, were found to keep 12.5% of the protein used in encapsulation without losing its activity.

DOI： 10.1080/02652040701644752

両親媒性マイクロチューブによって安定化されたPickeringエマルションの調製査読

鈴木生, 三觜幸平, 瓦吹亮, 岩永真一, 大久保貴広, 酒井秀樹, 小石眞澄, 阿部正彦

材料技術 25 ( 4 ) 153 - 159 2007年

W/O型エマルションの水相中への着色剤分散剤の添加効果査読

奥田貞直, 大久保貴広, 酒井秀樹, 阿部正彦

材料技術 25 ( 4 ) 160 - 169 2007年

Room temperature synthesis of crystalline mesostructured titania particles using Gemini-type surfactants as templates 査読

M. Abe, H. Shibata, K. Tsubone, H. Mihara, T. Sakai, K. Torigoe, S. Dai, T. Ohkubo, S. Utsumi, K. Sakamoto, M. Matsumoto, H. Sakai

色材協会誌 80 ( 11 ) 450 - 452 2007年

疎水内表面と親水外表面を有する両親媒性マイクロチューブの調製と特製査読

三觜幸平, 瓦吹亮, 鈴木生, 岩永真一, 大久保貴広, 酒井秀樹, 小石眞純, 阿部正彦

材料技術 25 ( 3 ) 127 - 134 2007年

Adsorption and aggregation properties of heterogemini surfactants containing a quaternary ammonium salt and a sugar moiety 査読

Kanae Nyuta, Tomokazu Yoshimura, Koji Tsuchiya, Takahiro Ohkubo, Hideki Sakai, Masahiko Abe, Kunio Esumi

LANGMUIR 22 ( 22 ) 9187 - 9191 2006年10月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

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.

DOI： 10.1021/la061688h

Polymerizable cationic gemini surfactant 査読

Masahiko Abe, Kazuyuki Tsubone, Takaaki Koike, Koji Tsuchiya, Takahiro Ohkubo, Hideki Sakai

LANGMUIR 22 ( 20 ) 8293 - 8297 2006年9月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

A polymerizable cationic gemini surfactant, [CH(2)dC(CH3) COO(CH2)(11)N+ CH3)(2)CH2]2 center dot 2Br(-), 1 has been synthesized and its basic interfacial properties were investigated (in water and in the presence of 0.05 M NaBr). For comparison, the properties of monomeric surfactant corresponding to 1, CH(2)dC(CH3) COO(CH2)(11)N+(CH3)(3)center dot Br-, 2, were also investigated. Parameters studied include cmc (critical micelle concentration), C-20 (required to reduce the surface tension of the solvent by 20 mN/m), gamma(cmc) (the surface tension at the cmc), cmc (the maximum surface excess concentration at the air/water interface), A(min) (the minimum area per surfacatant molecule at the air/water interface), and cmc/C-20 ratio (a measure of the tendency to form micelles relative to adsorb at the air/water interface). For the polymerizable gemini surfactant, 1, the methacryloxy groups at the terminal of each hydrophobic group in a molecule have no contact with the air/water interface in the monolayer, whereas for the corresponding monomeric surfactant, 2, the methacryloxy group contacts at the interface forming a looped configuration like a bolaamphiphile. Polymerized micelles of the gemini surfactant are fairly small monodisperse and spherical particles with a mean diameter of 3 nm.

DOI： 10.1021/la060156y

Preparation and photocatalytic activity of titania particulate film with mesostructured silica as binder 査読

Hirobumi Shibata, Takahiro Ohkubo, Hiroki Kohno, Pramoch Rangsunvigit, Hideki Sakai, Masahiko Abe

JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY 181 ( 2-3 ) 357 - 362 2006年7月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCIENCE SA

TiO2 (titania) particulate films with mesostructured silica (SiO2) as binder were prepared by drying glass substrate coated with an aqueous mixture of titania. particles, tetramethoxysilane (TMOS) and cetyltrimetylammonium bromide (CTAB) at appropriate temperature. X-ray diffraction (XRD) and IR absorption measurements on the obtained films revealed the formation of titania particles/silica composite thin film. XRD patterns at low angle region on these films indicated silica binder has well-ordered lamellar type mesostructure. These films show characteristic properties on both high absorption ability and photocatalytic activity to oxidative degradation of gaseous 2-propanol. (c) 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jphotochem.2005.12.018

孔版印刷に及ぼすW/O型エマルション中の着色剤の存在位置査読

奥田貞直, 大久保貴広, 酒井秀樹, 阿部正彦

MATERIALS TECHNOLOGY 24 ( 4 ) 222 - 230 2006年7月

Preparation and formation mechanism of mesoporous titania particles having crystalline wall 査読

H Shibata, H Mihara, T MLikai, T Ogura, H Kohno, T Ohkubo, H Sakait, M Abe

CHEMISTRY OF MATERIALS 18 ( 9 ) 2256 - 2260 2006年5月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

Mesoporous titania particles having anatase-type crystalline wall were prepared using a low-temperature crystallization technique. Crystalline mesoporous titania was obtained through the sol-gel process of titanium oxysulfate sulfuric acid hydrate (TiOSO4 center dot xH(2)SO(4)center dot xH(2)O) at 333 K in the presence of cetyltrimethylammonium bromide (C16TAB), a cationic surfactant. The mesoporous titania with hexagonal structure was formed according to the following mechanism. Nuclei of ultrafine titanium hydroxide oxide (TiO(OH)(2)) were formed from TiOSO4 on the periphery of the surface of cationic C16TAB micelles at the rimary stage of sol-gel reaction. Then, heat treatment at 333 K induced the transformation of the particle wall from TiO(OH)(2) to anatase nanocrystal, which resulted in the formation of mesoporous titania with a crystalline wall. Moreover, the presence of bromide ion (Br-), the counterion of C16TAB, was shown to suppress the collapse of mesostructure by retarding the transition from anatase to rutile.

DOI： 10.1021/cm0524042

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