研究者詳細 - 中原　佳夫

論文 - 中原　佳夫

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Analytical and Separation Chemistry by Taking Advantage of Organic Photochromism Combined with Macrocyclic Chemistry

Keiichi Kimura, Yoshio Nakahara

ANALYTICAL SCIENCES ( JAPAN SOC ANALYTICAL CHEMISTRY ) 25 ( 1 ) 9 - 20 2009年01月 [査読有り]

Photochromic crown compounds, such as monomeric and polymeric crown compounds incorporating spirobenzopyran, spironaphthooxazine, spirobenzothiapyran, Malachite Green, and Crystal Violet moieties, were synthesized for applications in the fields of analytical and separation chemistry. The photochromic crown compounds, especially crowned spirobenzopyran derivatives, were applied to metal ion extraction, extraction spectrophotometry, membrane transport, and ion chromatography, the sensitivity and selectivity of which were controlled and enhanced photochemically. Also, micelles and vesicles containing lipophilic crowned spirobenzopyrans and Malachite Greens were tested for their usefulness in spectrophotometric and fluorometric metal-ion determination and photocontrol of organic substance in aqueous systems. The polymeric crowned spirobenzopyrans were tried to use as a photochemical valve based on photochemical rheology changes. Moreover, attempts were made to directly observe photoinduced aggregation of the spirobenzopyran moiety and photoresponsive rheology changes of the polymeric crowned spirobenzopyran, by using chemical force microscopy.

DOI

Molecular design of tetraazamacrocyclic derivatives bearing a spirobenzopyran and three carboxymethyl moieties and their metal-ion complexing behavior

Koji Machitani, Hidefurni Sakamoto, Yoshio Nakahara, Keiichi Kimura

ANALYTICAL SCIENCES ( JAPAN SOC ANALYTICAL CHEMISTRY ) 24 ( 4 ) 463 - 469 2008年04月 [査読有り]

Tetraazacyclododecane and tetraazacyclotetradecane derivatives bearing a spirobenzopyran and three carboxymethyl moieties, I and 2, and a diethylenetriamine derivative bearing a spirobenzopyran and four carboxymethyl moieties 3 were synthesized. The isomerization behaviors based on the spirobenzopyran moiety of these ligands were studied by UV-visible spectrophotometry in aqueous solutions containing various metal ions at neutral pH. These ligands formed stable 1:1 complexes with lanthanide ions, while the spirobenzopyran moiety was isomerized to its corresponding merocyanine form even under dark conditions. In aqueous solutions containing a lanthanide ion, the absorption spectra of 1 or 2 showed remarkable blue shifts, while absorbances at the maximum absorption wavelengths in the visible region were enhanced; such changes are attributable to the isomerization to the merocyanine form of the spirobenzopyran moiety. These results suggest that the phenolate anion of the merocyanine moiety interacts very strongly with a lanthanide ion bound by the complexing moiety because of the high charge density of lanthanide ions. In contrast, the absorbance of merocyanine form was decreased by the complexation of the macrocyclic ligand with transition metal ions, such as Cu2+ and Zn2+. This result indicates that macrocyclic ligands, 1 and 2, formed complexes with transition metal ions only by the aminocarboxylate moieties, and the phenolate ion of merocyanine moiety was not able to participate in the complexation. This conclusion was also demonstrated by density functional theory calculations.

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Photoinduced micelle-to-vesicle transition and encapsulation of glucose by photoresponsive Malachite Green leuconitrile derivative

Ryoko M. Uda, Tomoyuki Tanabe, Yoshio Nakahara, Keiichi Kimura

SOFT MATTER ( ROYAL SOC CHEMISTRY ) 4 ( 3 ) 560 - 563 2008年 [査読有り]

DOI

De-tert-butylation of p-tert-Butylcalix[4]arene Using Sulfated Zirconia as a Solid Superacid Catalyst

M. Takagaki, E. Nomura, T. Kobata, H. Mori, Y. Nakahara, H. Taniguchi, K. Kimura

ITE-IBA Letters on Batteries, New Technologies & Medicine ( 1 ) 388 - 391 2008年 [査読有り]

Facile synthesis of C-2-Symmetric chiral crown ethers with two reactive hydroxymethyl groups

Yohji Nakatsuji, Yoshio Nakahara, Katsumori Nagamiya, Yuki Itoh, Kentaro Uesugi, Naohisa Ishida, Masahiro Muraoka, Toshiyuki Kida, Mitsuru Akashi

SYNTHESIS-STUTTGART ( GEORG THIEME VERLAG KG ) ( 19 ) 2973 - 2978 2007年10月 [査読有り]

DOI

Fabrication of celtular multilayers with nanometer-sized extracellular matrix films

Michiya Matsusaki, Koji Kadowaki, Yoshio Nakahara, Mitsuru Akashi

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION ( WILEY-V C H VERLAG GMBH ) 46 ( 25 ) 4689 - 4692 2007年 [査読有り]

DOI

Fabrication and enzymatic degradation of fibronectin-based ultrathin films

Yoshio Nakahara, Michiya Matsusaki, Mitsuru Akashi (担当区分：筆頭著者 )

JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION ( VSP BV ) 18 ( 12 ) 1565 - 1573 2007年 [査読有り]

Novel fibronectin (FN)-based ultrathin films were prepared by layer-by-layer (LbL) assembly. Among the various combinations of extracellular matrix (ECM) proteins and glycosamino-glycans (GAGs) such as FN, gelatin (G), alpha-elastin (E) and heparin (Hep), FN/Hep, FN/G and FN/E nanofilms were successfully fabricated in phosphate buffer solutions (pH 7.4). The film thickness of the nanofilms, in which each component can interact with each other by FN-specific interactions, was larger than that of other LbL films (E/Hep, G/E and G/Hep) prepared by electrostatic interactions. The FN/G film was rapidly decomposed by treatment with elastase, thus demonstrating, the enzymatic biodegradability of the nanofilm. We prepared the FN/heparinoid multilayers composed of FN and dextran sulfate (Dex), and its thickness was much larger than that of the FN/alpha-poly(L-lysine hydrochloride) (PLL) film prepared by LbL assembly using common electrostatic interactions. Furthermore, the FN/G and FN/Dex nanofilms prepared by FN-specific interaction were more stable in Eagle's MEM with 10% fetal bovine serum (FBS) than the electrostatic assembling films, FN/PLL and PLL/Dex. FN-based multilayers composed of FN and ECM components can be useful as artificial ECM films for tissue engineering and other biomedical applications.

PMSE 160-Design and characterization of novel membrane materials from imidazolium-based room temperature ionic liquids and liquid crystal structures

Michiya Matsusaki, Yoshio Nakahara, Mitsuru Akashi

ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY ( AMER CHEMICAL SOC ) 232 545 - 545 2006年09月 [査読有り]

3D-cell assembly by preparing of polymeric nanofilms on cell surface

Michiya Matsusaki, Yoshio Nakahara, Mitsuru Akashi

Polymer Preprints, Japan 55 ( 2 ) 5397 - 5398 2006年

Controlling of 3D-cell assembly for in vitro tissue engineering by bio-nanofilms

Michiya Matsusaki, Yoshio Nakahara, Mitsuru Akashi

Polymer Preprints, Japan 55 ( 1 ) 1994 2006年

We have studied 3D-cell assembly by preparing of nano-sized extra cellular matrix (bio-nanofilm) onto cell surface as novel cell assembling technology for tissue engineering field. Alternate immersion of adhered 1 st layer cells into fibronectin and gelatin/Tris buffer solution can prepare nano-ECM onto cell surfaces. 2 nd layer cells can adhere and extend onto bio-nanofilm. Continuation of these steps, 3D-cell layers can be fabricated. We have successfully prepared mouse L929 fibroblast and human SMC four layers by preparing of 15-20 nm of bio-nanofilm. The 3D-cell assembly technology would be useful for not only fabricating of vessel or skin like cell layers but also clarification of basic science of ECM for cell lamination.

Formation of protein nano-films for in vitro tissue engineering

Yoshio Nakahara, Michiya Matsusaki, Mitsuru Akashi

Polymer Preprints, Japan 55 ( 1 ) 1993 2006年

The development of multilayer ultrathin films containing proteins (bio-nanofilm) is one of the focal subjects in biomaterials science and technology. In particular, a layer-by-layer (LbL) assembly via bio-specific interactions for the immobilization of proteins onto a substrate has attracted much attention as driving forces due to their high affinity and specificity. In this study, the various combinations of LbL assemblies among extracellular matrix proteins and glycosaminoglycans including fibronectin (FN), gelatin (G), α-elastin (E), heparine (Hep), and dextrane sulfate (Dex) were analyzed quantitatively by a quartz crystal microbalance (QCM). And then, their enzymatic degradation behaviors and stabilities in cell culture medium (E-MEM + FBS) were investigated. In addition, it was confirmed that such bio-nanofilms could be formed on a phospholipid bilayer, which is postulated as a model of cell membranes.

Fluorometric sensing of alkali metal and alkaline earth metal cations by novel photosensitive monoazacryptand derivatives in aqueous micellar solutions

Y Nakahara, T Kida, Y Nakatsuji, M Akashi

ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY ( AMER CHEMICAL SOC ) 230 U3013 - U3014 2005年08月 [査読有り]

DOI

New fluorescence method for the determination of the critical micelle concentration by photosensitive monoazacryptand derivatives

Y Nakahara, T Kida, Y Nakatsuji, M Akashi (担当区分：筆頭著者 )

LANGMUIR ( AMER CHEMICAL SOC ) 21 ( 15 ) 6688 - 6695 2005年07月 [査読有り]

A novel fluorescence method for the determination of the critical micelle concentration (cmc) is reported. The cmc values of nonionic and anionic surfactants were evaluated utilizing a photosensitive monoazacryptand-Ba2+ complex, whose fluorescence intensity is sensitively changed by environmental conditions based on the photoinduced electron transfer (PET) mechanism as a fluorescent probe (PET method). Based on a comparison of the cmc values obtained by the PET method versus those obtained by conventional fluorescence-based methods as well as the values reported in the literature, one can conclude that the PET method is useful for the cmc determination. In particular, the PET method was more effective for the cmc determination of nonionic surfactants with very low cmc values (< 10(-5) M) than any other fluorescence-based method. In the cases of anionic surfactants, the PET method revealed the formation of the premicellar aggregates comprised of surfactant molecules and fluorescent probes below the cmc. Moreover, the hydrophobicity around the monoazacryptand-Ba2+ complex incorporated into various nonionic surfactant micelles was evaluated by this PET method.

DOI

Novel C-2-symmetric chiral 18-crown-6 derivatives with two aromatic sidearms as chiral NMR discriminating agents

Y Nakatsuji, Y Nakahara, A Muramatsu, T Kida, M Akashi

TETRAHEDRON LETTERS ( PERGAMON-ELSEVIER SCIENCE LTD ) 46 ( 25 ) 4331 - 4335 2005年06月 [査読有り]

DOI

Fluorometric sensing of alkali metal and alkaline earth metal cations by novel photosensitive monoazacryptand derivatives in aqueous micellar solutions

Y Nakahara, T Kida, Y Nakatsuji, M Akashi (担当区分：筆頭著者 )

ORGANIC & BIOMOLECULAR CHEMISTRY ( ROYAL SOC CHEMISTRY ) 3 ( 9 ) 1787 - 1794 2005年 [査読有り]

Novel monoazacryptand-type fluorescent chemosensors, I (derived From an 18-crown-6) and 2 (derived from a 15-crown-5) both with a pyrene ring as their photoresponsive moiety, were synthesized. Their fluorescence properties for alkali metal and alkaline earth metal cations in water were then examined. The detection of metal cations was accomplished by a change in the fluorescence intensity of the host compounds, based on a photoinduced electron transfer (PET) mechanism. In aqueous solution, I showed little fluorescence upon the addition of Ba2+ because of the very weak complexation with Ba2+, but the presence of micelles of polyoxyethylene(10) isooctylphenyl ether (Triton X-100) enabled I to show highly sensitive and selective Ba2+ detection among alkali metal and alkaline earth metal cations. With respect to the selective fluorescent detection of important metal cations (Na+, K+, Mg2+, Ca2+) relevant to living organisms, 2 was found to detect K+ with high selectivity in aqueous micellar solutions of polyoxyethylene(20) sorbitan rnonostcarate (Tween-60). The selectivity for metal cations was mainly dependent oil the goodness of fit of the host cavity and the metal cation size. In the presence of anionic surfactants, 2 detectcd alkaline earth metal cations mori effectively than alkali metal cations.

DOI

Synthesis of double-armed lariat ethers with pyrene moieties at each end of two sidearms and their fluorescence properties in the presence of alkali metal and alkaline earth metal cations

Y Nakahara, T Kida, Y Nakatsuji, M Akashi (担当区分：筆頭著者 )

JOURNAL OF ORGANIC CHEMISTRY ( AMER CHEMICAL SOC ) 69 ( 13 ) 4403 - 4411 2004年06月 [査読有り]

Two types of double-armed lariat ether derivatives having pyrene moieties at each end of two sidearms, (3x + 1)-crown-x derivatives 1 (x = 5), 2 (x = 6), and 3 (x = 4) (type A) and 3y-crown-y derivatives, 6 (y = 5) and 7 (y = 6) (type B), were synthesized, and their complexation behavior toward alkali metal and alkaline earth metal cations was examined by fluorescence spectroscopy. Pyrene excimer emission decreased accompanied by an increase in monomer emission upon metal ion complexation. This finding is ascribed to the change of the spatial distance of two pyrene rings by movement suppression of both the crown ring and one of the two sidearms based on complexation with the metal cation. The selectivity for alkaline earth metal cations was highly dependent on the fitness of the host cavity and the guest size. Although most of the fluorophores did not respond to alkali metal cations, only trans-7a containing an 18-crown-6 ring showed K+ selectivity.

DOI

A novel fluorescent indicator for Ba2+ in aqueous micellar solutions

Y Nakahara, T Kida, Y Nakatsuji, M Akashi (担当区分：筆頭著者 )

CHEMICAL COMMUNICATIONS ( ROYAL SOC CHEMISTRY ) pp 224-225 ( 2 ) 224 - 225 2004年01月 [査読有り]

DOI

Fluorometric sensing of alkaline earth metal cations by new lariat ethers having plural pyrenylmethyl groups on the electron-donating sidearms

Y Nakahara, Y Matsumi, WB Zhang, T Kida, Y Nakatsuji, Ikeda, I (担当区分：筆頭著者 )

ORGANIC LETTERS ( AMER CHEMICAL SOC ) 4 ( 16 ) 2641 - 2644 2002年08月 [査読有り]

[GRAPHICS]
New fluorescent compounds (1), lariat ethers having plural pyrenylmethyl groups on the sidearms, were prepared, and their complexation behavior with alkaline earth metal cations was examined by fluorescence spectrometry. The pyrene excimer emission decreased accompanied with an increase in the monomer emission upon complexation with the metal ion. This finding is ascribed to the cooperative participation of one of the two sidearms in the complexation of the crown ring with the metal ion.

DOI

Adsorption Mechanism of Poly (Ammonium Carboxylate) onto Phthalocyanine Blue Pigment Deduced by 1H NMR Spin-Lattice Relaxation Time

Taizo Mohri, Yoshio Nakahara, Wanbin Zhang, Toshiyuki Kida, Yohji Nakatsuji, Isao Ikeda

Journal of Oleo Science 50 ( 11 ) 857 - 863 2001年 [査読有り]

1H NMR spin-lattice relaxation time of ethylenediammonium dioctanoate (EDADO), a model dispersant (MD) for phthalocyanine blue (PhB) pigment, was examined with a high-resolution magic angle spinning (MAS) 1H NMR probe (1H Nano-nmrTM Probe). The adsorption mechanism of EDADO onto PhB was discussed on the basis of the spin-lattice relaxation time obtained by changing the polarity of the solvent and the temperature in the 1H NMR measurement. In addition to the deduction shown in our previous report that the adsorption of the MD molecule onto the pigment is induced by the coordination of a lone electron pair of a nitrogen atom of the amino group onto Cu (II) of PhB, it became clear that equilibrium among a diammonium salt, a half-salt, and diamine (ethylenediamine, EDA) is an important factor in the adsorption behavior. A comparison of measurements in chloroform-d and in methanol-d4 suggests that the complex of PhB and a half-salt composed of EDA and octanoic acid still has interaction with a carboxylic acid molecule through proton-transfer from the carboxylic acid to PhB (PhB of the complex and/or free PhB) and successive hydrogen bonding which may effect the dispersion of pigment in a nonpolar medium. The results obtained in this model system may afford a basis for explaining the good dispersing ability of poly (ammonium carboxylate), that is, polymeric dispersants in practical use. © 2001, Japan Oil Chemists’ Society. All rights reserved.

DOI

Study on the Adsorption Behavior of Dispersants onto Pigment Using 1H NMR Spin-Lattice Relaxation Time

Taizo Mohri, Yoshio Nakahara, Wanbin Zhang, Toshiyuki Kida, Yohji Nakatsuji, Isao Ikeda

Journal of Oleo Science 50 ( 8 ) 623 - 631 2001年 [査読有り]

In order to obtain information concerning the function of the polar group of polymeric dispersants generally used for pigment particles in a non-aqueous medium, alkylamine, alkylammonium salt, amide, and carboxylic acid were selected as the model dispersants and their adsorption behavior onto the phthalocyanine blue (PhB) pigment was studied by means of 1H NMR spin-lattice relaxation time using a high-resolution magic angle spinning 1H NMR probe. The amino group, particularly the primary amino group, was found to be the most effective as the adsorption site for the pigment among the functional groups examined in this study. The results obtained in this work suggest that the coordination of a lone electron pair on the nitrogen atom of an amino group to the Cu(II) of PhB is the driving force for the adsorption. © 2001, Japan Oil Chemists’ Society. All rights reserved.

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