担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acsapm.1c01315

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3389/fceng.2021.742447

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acsomega.0c06173

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Society of Mechanical Engineers  

DOI： 10.1299/jsmermd.2021.1p2-k05

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/d0ra07948k

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s00396-020-04705-5

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c9sm02213a

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.langmuir.9b00181

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/macp.201900021

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その他リンク： https://onlinelibrary.wiley.com/doi/full-xml/10.1002/macp.201900021

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.langmuir.8b04169

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.langmuir.8b02822

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acsami.7b03453

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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 BV  

Metal-coated microcapsules with tunable magnetic properties, which contained liquid cores and metallic Ni-P alloy shells, were synthesized via electroless plating. The fabrication process consisted of emulsification, phase separation, and electroless Ni plating stages. The material composition and sizes of Ni single crystals in the obtained metallic shells depended on the pH of the plating solution. It was found that the microcapsules prepared at high pH values (8.0 and 10.0) were characterized by ferromagnetic properties, whereas those synthesized at low pH values (4.7 and 6.0) were superparamagnetic. The produced micro capsules have potential applications as magnetic responsive carriers of phase change materials, which can be easily transferred to a desired place by applying external magnetic field. (c) 2017 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.mseb.2017.04.009

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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 BV  

Reverse micelles are thermodynamically stable systems, with a capacity to encapsulate hydrophilic molecules in their nanosized core, which is smaller than the core generally obtained with water in -oil-emulsion droplets. Herein, we present a simple technique for the preparation of poly(ethylene glycol)-block-polylactide (PEG-b-PLA) nanocapsules encapsulating a hydrophilic photosensitizer (indocyanine green, ICG), which exploits reverse micelle formation and subsequent emulsion-solvent diffusion. We establish the effect of the PEG-b-PLA composition and the co-surfactant volume on the diameter and water content of the reverse micelles. We demonstrate that the composition of PEG-b-PIA affects also the diameter and encapsulation efficiency of the resulting nanocapsules. We show that the ICG-laden nanocapsulescon fabricated under the most optimal conditions have a diameter of approximately 100 nm and an ICG encapsulation efficiency of 58%. We believe that the method proposed here is a promising step towards the preparation of hydrophilic drug-laden polymer nanocapsules with a small diameter and therefore suitable for use in drug delivery applications based on enhanced permeability and retention (EPR) effect-driven passive targeting. (C) 2017 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.colsurfa.2017.02.039

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

Conversion of recalcitrant lignocellulosic biomass to renewable and valuable biopolymers has attracted global interest to build up sustainable societies. Delignification of biomass for separating such biopolymers (e.g., cellulose and lignin) has been used as an efficient process. However, conventional delignification methods suffer from considerable drawbacks and cannot be considered as clean processes. In this study, a new type of polyoxometalate (POM) ionic liquid (IL), [(C6N2H11)(42)][Mo132O372 (CH3COO)(30)(H2O)(72)].ca 284 H2O ([1-ethyl-3-methylimidazolium] [Mo132O372 (CH3COO)(30) (H2O)(72)].ca 184 H2O) (abbreviated as [emim]POM), was synthesized and employed as a catalyst in the delignification of wood biomass. The synthesized [emim]POM catalyst was characterized by CNH analysis, Fourier transform infrared spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. The results indicated that the 1-ethyl-3-methylimidazolium [emim] group was appended to a (NH4)(42) [Mo132O372(CH3COO)(30) (H2O)(72)].ca 120 H2O POM precursor in which the [emim] group replaced the ammonium group. The [emim]POM catalyst effectively delignified wood in an IL [emim][OAc] (1-ethyl-3-methylimidazolium acetate) system: The lignin content of the produced cellulose-rich material was ca. 7.0 %, much lower than the 32.0 % lignin content of the untreated wood biomass. The delignification efficiency was improved by optimizing IL catalyst loading, the IL concentration, and the reaction conditions. This POM-based IL could be used in the delignification of lignocellulosic biomass to isolate cellulose and lignin for further chemical and mechanical processing.

DOI： 10.1007/s00226-016-0844-y

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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 BV  

The effects of photo-triggered tumor vascular treatment (PVT) on the structural and functional properties of tumor vasculature were assessed in Colon-26 (C26) and B16/BL6 (B16) tumor-bearing mice. Furthermore, anti-tumor efficacy of subsequently injected PEG liposomal paclitaxel (PL-PTX) was also evaluated. As a photosensitizer, a hydrophobic porphyrin derivative was used and formulated in polymeric nanoparticle composed of polyethylene glycol-block-polylactic acid to avoid its non-specific in vivo disposition. In the mice bearing C26 with high permeable vasculature, the prominent anti-tumor activity was confirmed by PVT alone, but the subsequently injected PL-PTX did not show any additive effect. PVT itself initially induced apoptotic cell death of tumor vascular endothelial cells and platelet aggregation, which would have subsequently induced apoptosis of C26 tumor cells surrounding the vasculature. On the other hand, in the mice bearing B16 with low permeable vasculature, PVT enhanced the anti-tumor activity of subsequently injected PL-PTX, which would be attributed to the tumor disposition amount and area of PEG liposomes enhanced by PVT. These results clearly indicated that the treatment would have made it possible to provide more efficient extravasation of PL-PTX, leading to its more potent anti-tumor effect. (C) 2015 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jconrel.2014.12.038

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：John Wiley and Sons Ltd  

BACKGROUND: Subcritical water treatment is considered an environment-friendly method to liquefy biomass to prepare valuable chemicals. Several researchers have studied the solid obtained after autohydrolysis treatment for use as reinforcement in biocomposities and was the base pulp and paper technologies. The novelty of this present research is the use of solid in the manufacture of starch foams. RESULTS: Subcritical water was used to extract hemicellulosic carbohydrate from walnut shells at temperatures from 160 to 260°C for 15min and at 200°C for various treatment times. The maximum yield was obtained at 200°C for 15min. The residue of the walnut shells obtained at the maximum carbohydrates extraction yield was used to prepare a biodegradable foam by compounding with corn starch using a technique similar to compression molding. It was found that replacing 20% of the corn starch by the residue had no deleterious effects on the density and morphology, as indicated by scanning electron microscopy. The prepared foams had a dense outer skin and a less dense interior with large, mostly open cells. The flexural strains were similar to that of foamed polystyrene and the flexural modulus and flexural stresses were larger. CONCLUSION: It was considered that the prepared biodegradable foam was a promising material to take the place of plastic products in the future.

DOI： 10.1002/jctb.4451

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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  

We report the controlled formation of internally porous polyelectrolyte particles with diameters ranging from tens to hundreds of micrometers through selective solvent extraction using microfluidics. Solvent-resistant microdevices, fabricated by frontal photopolymerization, encapsulate binary polymer (P)/solvent (Si) mixtures by a carrier solvent phase (C) to form plugs with well-defined radii and low polydispersity; the suspension is then brought into contact with a selective extraction solvent (S2) that is miscible with C and Si but not P, leading to the extraction of Si from the droplets. The ensuing phase inversion yields polymer capsules with a smooth surface but highly porous internal structure. Depending on the liquid extraction time scale, this stage can be carried out in situ, within the chip, or ex situ, in an external S2 bath. Bimodal polymer plugs are achieved using asymmetrically inverted T junctions. For this demonstration, we form sodium poly(styrenesulfonate) (P) particles using water (S1), hexadecane (C), and methyl ethyl ketone (S2). We measure droplet extraction rates as a function of drop size and polymer concentration and propose a simple scaling model to guide particle formation. We find that the extraction time required to form particles from liquid droplets does not depend on the initial polymer concentration but is rather proportional to the initial droplet size. The resulting particle size follows a linear relationship with the initial droplet size for all polymer concentrations, allowing for the precise control of particle size. The internal particle porous structure exhibits a polymer density gradient ranging from a dense surface skin toward an essentially hollow core. Average particle porosities between 10 and 50% are achieved by varying the initial droplet compositions up to IS wt % polymer. Such particles have potential applications in functional, optical, and coating materials.

DOI： 10.1021/la404506b

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：TRANS TECH PUBLICATIONS LTD  

Laccase Y20 (EC. 1.10.3.2) was coated with poly (ethylene glycol)-block-polylactide (PEG-PLA, M-W = 27680) via water-in-oil emulsion, and the activity and stability of the resulting PEG-PLA-laccase complex have been compared to those for the native laccase and lyophilized native laccase in an ionic liquid (IL) [C(2)mim][PF6] (1-ethyl-3-methylimidazolium hexafluorophosphate. The formation of spherical PEG-PLA-laccase complex of 330-480 nm was demonstrated by scanning electron microscopy. This polymer-laccase complex retained most of its enzymatic catalytic activity and exhibited excellent storage stability in IL, with over 70% of its initial activity retained after 12 days of storage in IL at 40 degrees C, whereas it was about 20% for native laccase under the identical conditions. This strategy could be employed to fabricate polymer based composites materials with novel biological functions.

DOI： 10.4028/www.scientific.net/AMM.625.333

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

A simple approach to preparing monodisperse poly(D, L-lactide) (PDLLA) microcapsules with a single aqueous core is developed. The method is based on automatic water-in-oil-in-water double emulsion formation from oil-in-water single emulsion via spontaneous emulsification which voluntarily disperses part of continuous aqueous phase into the dispersed oil phase dissolving oil-soluble amphiphilic diblock copolymer, poly(D, L-lactide)-b-poly(2-dimethylaminoethyl methacylate)(PDLLA-b-PDMAEMA), followed by coalescence of tiny water droplets within the polymer droplets, coupled with quick precipitation of polymers by diluting the emulsion with water. In this study, we have investigated the effect of PDLLA to PDLLA-b-PDMAEMA ratios and flow rates of each solution during preparing the emulsion on the final morphology and the size of the microcapsules. It was found that the polymer blend ratio played a crucial role in determining internal structure of the microcapsules. The microcapsules size decreased with the increment of the flow rate ratios of the continuous phase to the dispersed phase and eventually reached 10 mm, while maintaining narrow size distribution. In addition, we have demonstrated that the microcapsules can encapsulate both hydrophilic and hydrophobic compounds during the formation.

DOI： 10.1039/c3ra44066d

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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  

We describe a versatile and facile route to the continuous production of monodisperse polylactide (PLA) microcapsules with controllable structures. With the combination of microfluidic emulsification, solvent diffusion, and internal phase separation, uniform PLA microcapsules with a perfluorooctyl bromide (PFOB) core were successfully obtained by simply diluting monodisperse ethyl acetate (EA)-in-water emulsion with pure water. Rapid extraction of EA from the droplets into the aqueous phase enabled the solidification of the polymer droplets in a nonequilibrium state during internal phase separation between a concentrated PLA/EA phase and a PFOB phase. Higher-molecular-weight PLA generated structural complexity of the microcapsules, yielding core-shell microcapsules with covered with small PFOB droplets. Removal of the PFOB via freeze drying gave hollow microcapsules with dimpled surfaces. The core-shell ratios and the diameter of these microcapsules could be finely tuned by just adjusting the concentration of PFOB and flow rates on emulsification, respectively. These biocompatible microcapsules with controllable size and structures are potentially applicable in biomedical fields such as drug delivery carriers of many functional molecules.

DOI： 10.1021/la403883a

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記述言語：英語   出版者・発行元：WILEY-V C H VERLAG GMBH  

Polymeric micro- and nanoparticles receive the attention of researchers in different areas such as drug delivery, sensing, imaging, cosmetics, diagnostics, and biotechnology. However, processes with conventional equipment do not always allow precise control of their morphology, size, size distribution, and composition. On the other hand, microreaction technology offers improved control over the hydrodynamics, mass and heat transfer, allowing production of polymeric particles with better defined or new characteristics. Thus new horizons in polymer particle engineering arise from the use of microstructured or microfluidic devices. This article gives an insight into the latest developments and trends in the production of polymeric micro- and nanoparticles realized by microreaction technology directly.

DOI： 10.1002/mren.201300101

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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 SCI LTD  

Separation of cellulose fibers (CFs) from woody biomass with minimal structural alteration using a "green" and efficient method was achieved by treatment with the ionic liquid (IL), [emim][OAc] (1-ethyl-3-methylimidazolium acetate) at 80 degrees C for 1 h. The IL was recovered by rinsing with water-acetone mixture prior to treatment of the wood with Trametes sp. laccase in the presence of 1-hydroxybenzotriazole as a mediator. IL pretreatment did not significantly change the chemical composition of the wood, but did alter its structure and rendered its surface more accessible to the enzyme. Treated and untreated samples were characterized by SEM, FTIR, XRD, TGA, and chemical methods. The cellulose content of the produced fibers was approximately 73.1% and the lignin content was 9.8%, much lower than the lignin content of 29.3% of the untreated wood. The cellulose fibers exhibited higher cellulose crystallinity and better thermal stability compared to untreated wood materials. (C) 2012 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.biortech.2012.09.113

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Association of Solvent Extraction  

5-Hydroxymethylfurfural (HMF) was obtained from the dehydration of fructose under high temperature and pressure conditions (180 °C and 10 MPa). To avoid the decomposition of HMF in the bulk aqueous phase, we dehydrated fructose in the water / metyl isobuthyl ketone (MIBK) biphasic system. The HMF could be successfully extracted into the organic MIBK phase without further decomposition of HMF. We present a simplified model taking into consideration of the slug flow with the wall film to maximize the HMF yield in the MIBK phase. It was likely that the slug flow contributed to an increase in the surface-to-volume ratio for the mass transfer of HMF.

DOI： 10.15261/serdj.20.205

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

To develop potent paclitaxel (PTX) formulations for cancer chemotherapy, we formulated PTX into polymeric nanoparticles composed of polyethylene glycol (PEG) and polylactic acid (PLA) block copolymer (PN-PTX). First, the physicochemical properties of PN-PTX prepared were assessed; the mean particle size was around 80nm and the zeta potential was found to be almost neutral. Next, the in vitro PTX release property was assessed by a dialysis method. Although rapid release of PTX was observed just after dosing, around 70% of PTX was stably incorporated in polymeric nanoparticles for a long time in the presence of serum. Then, the in vivo pharmacokinetics of PN-PTX after intravenous administration was investigated in Colon-26 (C26) tumor-bearing mice. Both polymeric nanoparticles and PTX incorporated exhibited a long blood circulating property, leading to enhanced permeability and retention (EPR) effect-driven, time-dependent tumor disposition of PTX. Tumor distribution increased gradually for 24h, and tissue uptake clearance of polymeric nanoparticles in the liver and spleen was lower than that of PEG liposomes. Since these results indicated that the in vivo disposition characteristics of PN-PTX were very favorable, we then evaluated the anti-tumor effect of PN-PTX in C26 tumor-bearing mice. However, PN-PTX did not exhibit any significant anti-tumor effect, presumably due to the poor PTX release from polymeric nanoparticles. From these results, it is considered that the favorable pharmacokinetic properties of nanoparticles and the drug incorporated do not always lead to its potent in vivo pharmacological activity, suggesting the importance of PTX release properties within tumor tissues.

DOI： 10.1248/bpb.b12-0020

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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 BV  

The objective of this study was to provide a new environmentally friendly and efficient approach for isolating cellulose fibers with minimum structural alteration from wood biomass. The method comprised enzymatic delignification of ionic liquid (IL) swollen wood biomass in ILs-aqueous systems with the aim of overcoming low delignification efficiency associated with the difficulties in enzyme accessibility to the solid substrate and the poor substrate and products solubility in aqueous system. It was found that the cellulose rich wood fibers obtained from biological pretreatment in IL-aqueous systems contained significantly lower amounts of lignin as compared to those found in conventional methods. The treated wood fibers were characterized using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and X-ray diffractometry (XRD) and compared those with untreated wood fibers. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.bej.2011.11.001

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：IOP PUBLISHING LTD  

The aim of this research is to realize a small continuous flow system with emulsification devices. This system is designed for the generation of sub-micron or nano monodisperse emulsions. In this study, we have designed, fabricated, and evaluated a device that consists of a microchannel plate and an ultrasonic vibrating plate. This device can realize a continuous flow system and the plates are easily stacked. The oscillation frequency was 2.25 MHz. We succeeded in generating emulsions that have a diameter of 200 nm. We also designed the cross-sectional pattern of the microchannel of the ultrasonic device to increase residence time effectively. As a result, we have succeeded in obtaining emulsions that have a diameter of 80 nm. (C) 2011 The Japan Society of Applied Physics

DOI： 10.1143/JJAP.50.07HE24

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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  

Microfluidic liquid-liquid extraction of the ethyl ester of docosahexaenoic acid (DHA-Et) with silver ions was investigated using slug flow and a water-in-oil (W/O) emulsion as specific flow patterns possessing large interfacial areas. To compare the extraction rates of both systems, slug flow and a W/O emulsion with similar specific interfacial areas were prepared. Extraction rates for the systems were the same at 298 K However, at 268 K, slug flow had a faster extraction rate than the W/O emulsion. Theoretical calculation follows the results for both systems at 298 K and for the slug flow system at 268 K, suggesting that the emulsion stabilizer inhibits complex formation between DHA-Et and silver ions at the O/W interface. A reduction in extraction rate was observed in the slug flow system at 268 K when the emulsion stabilizer was used. Slug flow can be prepared without stabilizer, offering advantages over emulsions in microfluidic extraction.

DOI： 10.1021/ie102207c

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

Our previous research showed that a simple ultra-high-pressure process made poly(vinyl alcohol) (PVA) solution into a macrogel and nanoparticles. To investigate the release properties of PVA hydrogels prepared by the ultra-high-pressure treatment, we prepared hydrogels containing model drugs by pressurizing a PVA solution with Alfa-G Hesperidin or Oil Blue N as a water-soluble or an oil-soluble model drug, respectively. In the case of the oil-soluble drug, an oil-in-water emulsion, Oil Blue N containing dodecane in a PVA solution, was used by homogenization before pressurization. The average diameter and the diameter distribution of oil droplets before and after the ultra-high-pressure treatment were almost the same. However, the PVA hydrogel prepared at 10,000 atm for 10 min exhibited the slowest release rate of model drugs. Thus, we found that the release rates of the model drugs from the PVA hydrogels were controlled by the degree of crosslinking in the resulting gels, which was determined from the operation parameters of the ultrahigh-pressure treatment, such as the pressure, time, and concentration of the PVA solution. Therefore, an ultrahigh-pressure process is promising for drug-carrier development because of the nonharmful simple preparation process. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 119: 2725-2729, 2011

DOI： 10.1002/app.31622

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記述言語：英語   出版者・発行元：WILEY-V C H VERLAG GMBH  

DOI： 10.1002/cphc.201000905

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

Monodisperse polylactide (PLA) microspheres were continuously fabricated by microfluidic emulsification and subsequent dilution in water. The diameter was precisely tuned from 6 to 50 mu m by changing the flow rate of the fluids in microfluidics or the PLA concentration in the dispersed phase. The use of amphiphilic oil-soluble poly(ethylene glycol)-b-polylactide (o-PEG-PLA) as a matrix resulted in a highly porous microsphere morphology, and the porosity was controlled by blending PLA. Therefore, mono-disperse PLA microspheres with the predetermined surface porosity were continuously produced by just enough reagents and energy.

DOI： 10.1039/c1sm05910f

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

The liquid-liquid extraction dynamics of an ethyl ester of docosahexaenoic acid (DHA-Et) with silver ion was investigated. The kinetic model was derived according to the following stepwise processes: Diffusion of DHA-Et across the organic film, complex-formation between DHA-Et and silver ion at the interface, and diffusion of extracted complex across the aqueous film. The kinetic parameters for the complex-formation reaction were determined from the investigation with the stirred transfer cell. With the proposed model and determined parameters, we predicted the uptakes of DHA-Et for the extraction system utilizing a slug flow prepared by a microchip. The calculated uptakes showed good correlation to the experimental data. The theoretical investigation suggested that the fast equilibration realized for the slug flow extraction system was due to the large specific interfacial area of the slug caused by the presence of wall film and the thin liquid film caused by the internal circulation. © 2009 American Institute of Chemical Engineers.

DOI： 10.1002/aic.12132

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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 BV  

Poly(ethylene glycol)-block-polylactide (PEG-PLA) nanoparticles were prepared through the oil-in-water (O/W, ethyl acetate/water) emulsion technique using oil-soluble PEG-PLA in the presence of water-soluble PEG-PLA as a surfactant. The particle diameter decreased with increasing water-soluble PEG-PLA concentration, the smallest averaged diameter was 75 nm. From these results, it was found that water-soluble PEG-PLA acted as a surfactant which prevents further coalescence of droplets. In addition, the particles diameter decreased with increasing hydrophile-lipophile balance of oil-soluble PEG-PLA in the absence of water-soluble PEG-PLA. In contrast, the particle diameter was constant in the presence of water-soluble PEG-PLA. Therefore, the capability of water-soluble PEG-PLA as a surfactant was more excellent than that of oil-soluble PEG-PLA. (C) 2010 Elsevier B.V. All rights reserved

DOI： 10.1016/j.matlet.2010.01.076

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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 versatile biodegradable thermoresponsive polymer was developed. The polymer has succinimide and isopropylasparamide segments and exhibits a phase transition with thermoreversibility that can be controlled by changing the polymer composition. With fewer succinimide units, the polymer exhibits the type of thermo-reversible phase transition that is characteristic of poly(N-isopropylacrylamide) (PNIPAAm). The polymer with a higher proportion of succinimide units exhibits a thermo-irreversible phase transition, resulting in the formation of nanospheres that are stable below the transition temperature. The stable nanospheres are generated by dehydration and subsequent conformational stabilization through an interaction between imide rings. This thermoirreversible phase transition in water provides a simple, oil-free preparation of biodegradable nanospheres.

DOI： 10.1021/am900705s

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

The goal of this study is to realize an emulsification device for the generation of sub-micron size monodisperse emulsions. We have fabricated and tested the device which consists of a microchannel plate and an ultrasonic vibrating plate. The device can realize continuous flow system and those plates are easily stacked. We have succeeded in generating emulsions which has a diameter of 80 nm. ©2010 IEEE.

DOI： 10.1109/MHS.2010.5669586

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：IOP PUBLISHING LTD  

In this study, a device using an ultrasonic vibration and a microchannel has been developed to obtain emulsions. The process of generating emulsions involves a Y-type microchannel and an ultrasonic device. Once micron-sized emulsions were generated by the Y-type microchannel, the micron-sized emulsions were sonicated using ultrasonic vibration to produce emulsions. Although the diameter of emulsions was 30 mu m using the Y-type microchannel, the diameter of the sonicated emulsions was about 200 nm. In addition, as the applied voltage was increased, sonicated emulsions became smaller and the distribution became sharper. (C) 2010 The Japan Society of Applied Physics

DOI： 10.1143/JJAP.49.07HE13

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

Monodisperse poly(D,L-lactide) (PDLLA) microspheres were prepared by dispersion polymerization of D,L-lactide in xylene/heptane (1/2, v/v) with poly[(dodecyl methacrylate)-co-(2-hydroxyethyl methacrylate)] (P(DMA-co-HEMA)) as a dispersion stabilizer. P(DMA-co-HEMA) contains hydroxy groups, which act as an initiation group for pseudoanionic dispersion polymerization. The best coefficient of variation (CV) values concerning particle diameter distribution and the particle diameter of obtained PDLLA microspheres were 3.7% and 5.3 mu m, respectively. The particle diameter decreased with increasing concentration of P(DMA-co-HEMA) and HEMA maintained low CV (<10%) values. As a result, monodisperse PDLLA microspheres ranging from 1.3 to 5.3 mu m were obtained. In addition, it was found that monodisperse PDLLA microspheres were obtained by sufficient capture of growing polymers and monomers in the particle growth stage. Therefore, the HEMA concentration in P(DMA-co-HEMA) strongly affecting the capturing capability is the most important factor. (C) 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5230-5240, 2009

DOI： 10.1002/pola.23572

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

Poly(D,L-lactide) (PDLLA) microspheres with narrow diameter distribution were prepared by dispersion polymerization of D,L-lactide in xylene/heptane (1:2, v/v) using poly(dodecyl methacrylate)-g-poly(D,L-lactide) (PDMA-g-PDLLA) as a dispersion stabilizer. The particle diameters of PDLLA microspheres were controlled from 200 nm to 5 mu m by altering the concentration and the graft chain number of PDMA-g-PDLLA. The effect of the copolymer composition on the particle diameter was investigated to clarify an important factor of the copolymer structure for the control of the particle diameter. As a result, it was necessary for anchor block in diblock copolymer as a dispersion stabilizer to have low solubility in the solution rather than the compatibility with particles. Moreover, we confirmed by dynamic light scattering measurement that PDMA-g-PDLLA formed micelles in the solution. In conclusion, it was clarified that PDLLA microspheres with a wide range of particle diameter were prepared due to the different kinetic stability of micelles.

DOI： 10.1007/s00396-009-1998-z

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

To control particle diameter and particle diameter distribution in dispersion copolymerization of styrene and sodium polyaspartate macromonomer containing vinylbenzyl pendant groups, effects of some polymerization parameters, water contents, initiator concentration, styrene monomer concentration, reaction temperature, and type of initiator on the particle diameter and the diameter distribution were investigated. Variation of the water contents from 20 to 80 vol % controls the resultant particle diameter from 0.066 to 0.47 pm. The diameter increased with increasing initiator concentration. This tendency is similar to dispersion polymerization system using a nonpolymerizable stabilizer. Particle diameter distribution broadened with increasing styrene monomer concentration. This trend was attributed to the increase of a period of particle formation. This result indicated that the period of particle formation affected the resultant particle diameter distribution. Particle diameter distribution was successfully improved (CV = 9.1 from 23.6%) by shortening of decomposition time of initiator. (C) 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2281-2288, 2009

DOI： 10.1002/pola.23309

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-V C H VERLAG GMBH  

Monodisperse poly(D,L-lactide) (PDLLA) microspheres have been prepared by dispersion polymerization Of D,L-lactide with a synthetic polymeric stabilizer. The polymerization is carried out in xylene/heptane (1:2, v/v) at 368 K for 3 h with poly[(dodecyl methacrylate)-co-(2-hydroxyethyl methacrylate)] (P(DAAA-co-HEMA)). P(DMA-co-HEMA) has hydroxy groups as an initiation group for pseudoanionic dispersion polymerization. The particle diameter and the coefficient of variation concerning the diameter distribution of the obtained PDLLA microspheres are 3.9 mu m and 4.3%, respectively. In addition, from the results of dynamic light scattering measurements, it is found that P(DMA-co-HEMA) and the PDLLA-grafted copolymer form a micellar structure in solution.

DOI： 10.1002/marc.200800620

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

Sodium polyaspartate (PAspNa) derivatives with vinylbenzyl pendant groups (VBA-PAspNa) were synthesized by reaction of poly(succinimide) (PSI) and vinylbenzylamine (VBA), and hydrolysis by sodium hydroxide (NaOH) solution. VBA-PAspNa is a macromonomer with multiple vinyl groups in the side chain. Submicron sized polymeric particles were prepared by dispersion copolymerization of styrene with VBA-PAspNa in a mixture of ethanol and water. Particle diameter decreased with increasing concentration and vinyl group fraction of VBA-PAspNa. When compared with the particle diameter prepared using PAspNa or benzylamine-modified PAspNa (BA-PAspNa) as a dispersion stabilizer without vinyl groups, the particles prepared with VBA-PAspNa were an order smaller than those prepared with PAspNa or BA-PAspNa. The particles after refinement show an adequate negative zeta-potential. From this result, we clarified the presence of PAspNa chains anchored onto the particle surface. (C) 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 762-770, 2009

DOI： 10.1002/pola.23192

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

Sodium polyaspartate (PAspNa) macromonomer with an acryloyl end group was synthesized for dispersion polymerization. At first, a poly(succinimide) (PSI) derivative with a hydroxyphthalimide end group was synthesized by polycondensation of l-aspartic acid and 4-hydroxyphthalic acid. Then, the PSI derivative was end-capped with an acryloyl group by a reaction with acrlyloyl chloride. Finally, a PAspNa derivative with a vinyl end group was synthesized by a hydrolysis of succinimide units by sodium hydroxide. The synthesized macromonomer was applied as a polymerizable stabilizer in dispersion copolymerization of styrene in a mixture of ethanol and water. The PAspNa macromonomer acted as an effective stabilizer and gave sub-micron-sized polymeric particles in dispersion polymerization in polar medium.

DOI： 10.1007/s00396-008-1963-2

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

A novel micromixer with simple construction and excellent mixing performance is developed. The micromixer is composed of two stainless steel tubes with different diameters: one is an outer tube and another is an inner tube which fits in the outer tube. In this micromixer, one reactant fluid flows in the mixing zone from the inner tube and the other flows from the outer tube. The excellent mixing performance is confirmed by comparing the results of a Villermaux/Dushman reaction with those for the other micromixers. The developed micromixer has a mixing cascade with multiple means and an asymmetric structure to achieve effective mixing. The excellent mixing performance of the developed micromixer suggests that serial addition of multiple phenomena for mixing will give us an efficient micromixing.

DOI： 10.1039/b817536e

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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  

We demonstrate a simple, unique method for preparing microcapsules with holes in their shells. Cross-linked polymelamine microcapsules are prepared by the phase-separation method. The holey shell of each microcapsule is synthesized on the surface of an oil-in-water (O/W) emulsion droplet where a water-soluble polymeric surfactant and an oil-soluble surfactant are competitively adsorbed. The water-soluble polymeric surfactant provides a reaction site for shell formation. The oil-soluble surfactant molecules seem to self-assemble while the shells are being formed, so holes appear where they assemble. The critical degree of surface coverage of an emulsion droplet by the water-soluble polymeric surfactant needed to form the holey shells is determined to be 0.90 from theoretical calculations in which competitive adsorption is considered. Theoretical consideration suggests that the size and quantity of the holes in the microcapsule shells are controlled by the composition of the surfactants adsorbed on the surface of an emulsion droplet. This theoretical consideration is confirmed by experiments. The prepared microcapsule with controllable macroholes in its shell has the potential to be used for controlled release applications and can be used to fabricate a microcapsule that encapsulates hydrophilic compounds.

DOI： 10.1021/la800758d

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

We used poly(aspartic acid) (PAsp) synthesized by ion exchange with sodium polyaspartate (PAspNa) as a dispersion stabilizer. PAsp improved the dispersion stability and the solubility in the medium for dispersion polymerization. The effects of the stabilizer hydrophobicity on particle formation, conversion, particle diameter, and its distribution of polystyrene microspheres were investigated by using both biodegradable polymers as a dispersion stabilizer. According to these results, we concluded that the polymerization rate of the styrene with PAsp was higher than that of styrene with PAspNa. That is why, smaller and more monodisperse microspheres were prepared with PAsp, compared to those with PAspNa.

DOI： 10.1007/s00396-008-1924-9

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Monodisperse polymelamine microcapsules were prepared by phase separation method. Control of microcapsule diameter was investigated using the uniform-sized oil-in-water emulsion droplets as the capsule core. The monodisperse emulsion droplets were prepared using the Shirasu porous glass (SPG) membrane emulsification technique. The effects of the diameter of the oil droplet and concentration of sodium dodecyl sulfate (SDS), which is a typical emulsifier in SPG membrane emulsification, on microencapsulation were investigated. The microcapsules were aggregated when oil droplets with small size were microencapsulated at high SDS concentration. To reduce the SDS concentration, the creamed emulsion was used. The monodisperse polymelamine microcapsules were successfully prepared by using the creamed emulsion. The microcapsule diameter was almost similar to the diameter of the encapsulated oil droplet. The coefficient of variation values was about 10% for all microcapsules prepared in this study. Control of microcapsule diameter was achieved in the range of 5-60 μm. © Springer-Verlag 2008.

DOI： 10.1007/s00396-008-1837-7

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Controlling the noncovalent bondings such as electrostatic interaction, van der Waals force and hydrogen bond, is the key factor to generate molecular assembly. We show that pressure is one of the most intensive variables for controlling these intermolecular forces and producing assembled structure. Macrogel and nanoparticles of hydrogen-bonded polymers were simply obtained through an ultrahigh-pressure process. The morphology of the obtained assembly depends on concentration and various conditions of the pressurization. These results indicate that the ultrahigh-pressure induces inter/intra-hydrogen bond, which is strong enough to maintain microassemblies such as gels and particles. This methodology leads to the molecular design of pressure-induced molecular assembly, and nonharmful processes for molecular separation and drug development. © 2008 Wiley Periodicals, Inc.

DOI： 10.1002/polb.21407

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2008.0.613.0

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2008f.0.539.0

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2008f.0.614.0

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

By utilizing a microreactor, extraction of ethyl ester of docosahexaenoic acid (DHA-Et) and eicosapentaenoic acid (EPA-Et) from an organic solution into an aqueous silver nitrate solution has been investigated. Slug flow preapared by using a T-shape microreactor was used to extract DHA-Et and EPA-Et. Utilizing slug flow created large specific interfacial area between aqueous and organic phases, and ultra fast extraction has been achieved. Extraction of both DHA-Et and EPA-Et took less than 20 s to reach equilibrium. In all of the experiments, the amount of DHA-Et or EPA-Et extracted was the same to that expected from the batch experiment. These facts indicate that the microreactor system can realize an ultra-fast examination system of extraction equilibrium. In addition, by maintaining the temperature quite low, a drastic improvement of extraction ratio is exhibited under a low silver nitrate concentration condition. That is, it can easily cut down silver nitrate by utilizing a microreactor. This is preferable for the practical operation. Copyright © 2007 The Society of Chemical Engineers, Japan.

DOI： 10.1252/jcej.07WE144

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Wichtig Editore s.r.l.  

Introduction: The dialyzer apparatus has been widely used as an artificial kidney in medical treatment. However, side effects such as amyloidosis have occurred during long-term treatment. Therefore, we focused on developing a hybrid artificial kidney with a filtration and reabsorption apparatus, but it was found that cells spread extensively and it is difficult to maintain a uniform monolayer with a regular cell shape on a collagen-coated substrate. The purpose of this study was to improve cell adhesion, uniform stable monolayer formation and active transport function by immobilization of arginine-glycine-aspartic acid (RGD) on the culture substratum. Materials and Methods: Polycarbonate semipermeable membranes were coated with collagen, fibronectin, laminin and synthetic polypeptide, including RGD (Pronectin F). Cell adhesion and digoxin transport were estimated using a renal proximal tubule cell line that overexpressed the P-glycoprotein gene. Results and Discussion: Under initial and confluent conditions, immobilized cell density in Pronectin F-coated wells was higher than that under other conditions. Transepithelial electrical resistance and digoxin transport activity on Pronectin F-coated membranes were the highest of all conditions. This might have been caused by uniform cell morphology and high cell density. © Wichtig Editore, 2007.

DOI： 10.1177/039139880703000105

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2007.0.41.0

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2007.0.672.0

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2007.0.827.0

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2007f.0.74.0

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2007f.0.659.0

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JOHN WILEY & SONS INC  

A possible strategy for creating three-dimensional (3D) tissue-engineered organs in vitro with similar volumes to the primary organs is to develop a capillary network throughout the constructs to provide sufficient oxygenation and nutrition to the cells composing them. Here, we propose a novel approach for the creation of a capillary-like network in vitro, based on the spontaneous tube-forming activity of vascular endothelial cells (ECs) in collagen gel. We fabricated a linear tube of 500 mu m in diameter,the inner surface of which was filled with bovine carotid artery vascular endothelial cells (BECs), in type I collagen gel as a starting point for the formation of a capillary-like network. The BECs exposed to a medium containing vascular endothelial growth factor (VEGF) migrated into the ambient gel around the tube. After 2 weeks of VEGF exposure, the distance of the migration into the ambient gel in the radial direction of the tube reached approximately 800 pm. Cross-sections of capillary-like structures composed of the migrating BECs, with a lumen-like interior space, were observed in slices of the gel around the tube stained with hematoxylin-eosin (H&E). These results demonstrate that this approach using a pre-established tube, which is composed of ECs, as a starting point for a self-developing capillary-like network is potentially useful for constructing 3D organs in vitro. (c) 2006 Wiley Periodicals, Inc.

DOI： 10.1002/bit.20903

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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 INC  

Liposomes, which had entrapped bovine serum albumin (BSA), were modified with diglucosamine by two methods. The liposome was prepared by a freeze-thawing method in the presence of the disaccharide, or the disaccharide was added to the liposome prepared in advance without it. To examine the effects of diglucosamine, the morphology, mean particle size, and zeta potential of both liposomes were compared with those of BSA-entrapping liposome prepared without the disaccharide. Diglucosamine caused no remarkable change in shape and no aggregation of the liposome. The presence of the disaccharide was confirmed on the surfaces of modified liposomes, and the entrapment of BSA into the liposomes was increased by the disaccharide. The entrapment behavior was affected by the way the disaccharide was added, and the difference in the way the BSA was entrapped was also indicated.

DOI： 10.1080/08982100600680667

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

Liposomes composed of phosphatidylcholine (PC) and phosphatidylglycerol (PG) were prepared to examine the effects of lipid composition on surface properties of the liposomes and entrapment efficiency of proteins into the liposomes. Lipid composition was found to influence the amount and mode of proteins entrapped into the PC/PG liposomes, as well as the surface properties of the liposomes. Both electrostatic and non-electrostatic interactions between protein and liposome played important roles in the entrapment of protein into the PC-containing liposomes, and the amount of proteins adsorbed electrostatically on the PG-containing liposomes was also influenced by lipid composition. Copyright © 2006 The Society of Chemical Engineers, Japan.

DOI： 10.1252/kakoronbunshu.32.514

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2006f.0.994.0

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

We fabricated a scaffold of poly (lactic acid) and acidic gelatin, a sustained-release carrier of basic fibroblast growth factor (bFGF), which is a positive regulator of angiogenesis. After 1 week of implantation into mesentery of rats, blood vessels induced in the bFGF-containing scaffolds were almost double those in the bFGF-free scaffolds. Further, histological examination of hepatocyte-immobilizing scaffolds retrieved after 1 week of implantation into the mesentery of the rats that received a 70% hepatectomy revealed that the bFGF-containing scaffolds were more efficient for immobilized cell survival than the bFGF-free scaffolds. As well, hepatocytes in the bFGF-containing scaffolds kept their hepatospecific glycogen storage capacity.

DOI： 10.1252/jcej.38.913

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Agarose capsules were prepared using a droplet breakup method in a coflowing stream. Subsieve-size capsules 76±9 μm in diameter were obtained by extruding 4 wt% agarose solution from a needle (300 μm inner diameter) at a velocity of 1.2 cm/s into an ambient liquid paraffin flow of 20.8 cm/s. Increasing the flow rate of the liquid paraffin and decreasing that of the agarose solution resulted in a decreased resultant capsule diameter. Reduction in diameter from several hundred micrometers to subsieve-size (&lt
100 μm) enhanced molecular exchange and mechanical stability. Measurements based on the percentage of intact mitochondria in the cells demonstrated that the viability of the enclosed cells was independent of capsule diameter. No significant difference was observed between the viabilities of cells enclosed in capsules with diameters of 79±8 and 351±41 μm (p=0.43). Compared with cells seeded in a tissue culture dish, the cells enclosed in the subsieve-size capsules showed 89.2% viability. © 2004 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.biomaterials.2004.11.043

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Primary rat hepatocytes were co-cultured with bone marrow cells (BMCs) in a tissue culture-treated culture well (TCW) or a collagen-coated culture well (CCW). Although a medium containing serum was used, the co-cultured cells formed spheroids on the TCW within 2 days, and ammonia metabolism and albumin secretion activities were well maintained for 3 weeks. The co-cultured cells formed a monolayer on the CCW within 2 days, and liver functions were maintained for 3 weeks. The ammonia metabolism activities and albumin secretion activities of co-cultured cells on the CCWs were slightly inferior to those on the TCWs. This co-culture system of hepatocytes and BMCs is an appropriate culture system for the expression and maintenance of liver-specific functions in vitro, and is expected to be applicable to bioartificial liver systems, regenerative medicine, and liver function simulators. © The Japanese Society for Artificial Organs 2005.

DOI： 10.1007/s10047-005-0289-9

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Mechanical strength of cell-enclosing capsules governs the success of the transplantation of enclosed cells in vivo for cell therapy. Mechanical strength closely correlates with the concentration and molecular weight of the polymers present in the aqueous solution that end up in the capsules, and the viscosity of the aqueous polymer solution also depends on these two factors. Three aqueous solutions differing in viscosity (1.0, 36, and 194 mPa s) were extruded from a needle (300 μm inner diameter) at a velocity of 1.2 cm/s into an ambient co-flowing liquid paraffin laminar stream. Smaller droplets were obtained from a higher viscous solution. At a liquid paraffin velocity of 23.5 cm/s, the diameter of droplets obtained from the highest viscous solution (194 mPa s)) was 44 ± 4 μm, and it represented 40% and 20% of that from droplets in solutions of 36 and 1.0 mPa s viscosity, respectively. The cells enclosed in these droplets maintained more than 95% viability during the droplet breakup process independent of the viscosity of the aqueous solution (p &gt
0.50). In addition, retrieved cells from the droplets showed the same proliferation profiles as the cells that were not subjected to the droplet breakup process, on tissue culture dishes (p &gt
0.13). © 2005 American Chemical Society and American Institute of Chemical Engineers.

DOI： 10.1021/bp049600i

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

A hydrophilic ultrafiltration membrane, regenerated cellulose, facilitates the size-selectable permeability of hydrophilic solutes in reverse micellar solution. By using an ultrafiltration membrane with a molecular weight cutoff of 3,500, we demonstrate a nonaggregating protein refolding technique based on the dialysis of reverse micellar solution. This realizes concurrent removal of denaturants, urea and 2-mercaptoethanol, and the supply of redox reagents, reduced and oxidized glutathione (GSH, GSSG), to promote renaturation of proteins. Two mg/ml ribonuclease A (RNase A) was refolded completely without any dilution and aggregation for 60 h. The refolding behavior of RNase A is strongly influenced by the ratio of GSH and GSSG. Moreover, we recovered 90% of the refolded RNase A from AOT reverse micellar solution with acetone precipitation and β-cyclodextrin washing. These findings should facilitate the production of a continuous protein refolding membrane reactor. © 2004 Wiley Periodicals, Inc.

DOI： 10.1002/bit.20329

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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  

Several 10-cm-long capillary tubes [made of poly(ether ether ketone) (PEEK)] with inside diameters of 0.1-2.0 mm were filled with silica monolith-immobilized protease derived by in situ sol-gel transition from a 1:4 mixture of tetramethoxysilane and methyltrimethoxysilane. Transesterification between 20 mM (S)-(-)-glycidol and 0.4 M vinyl n-butyrate in an organic solvent was used as the test reaction. The substrate solution flowed through the column at a flow rate of 0.0004-5.0 mL(.)min(-1). The conversion in the micro-bioreactor was higher than that in the batch reactor at a high liquid flow rate. When three tubes were connected in series, the conversion at a fixed ratio of the mass of the enzyme to the liquid flow rate was increased by approximately 50%, because of the tripling of the flow rate as compared to the case with a single tube. Changes in the tube diameter had no influence on the conversion at a fixed superficial liquid velocity. Further, the conversion increased with a decrease in the enzyme content. These results were ascribed to the apparent effect of liquid-solid mass transfer and were analyzed quantitatively using a simple mathematical model.

DOI： 10.1021/ie049354f

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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  

The rupture forces of porous alginate scaffolds seeded with hepatocytes or fibroblast-like cells increased during 3 d of culture and then decreased. The phenomenon was independent of the number of viable cells within the scaffolds, but dependent on protein adsorption to the alginate as well as a reduction in the degree of crosslinks of the calcium-alginate gel. © 2005, The Society for Biotechnology.

DOI： 10.1263/jbb.100.127

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2005.0.319.0

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2005.0.204.0

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2005.0.318.0

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2005.0.212.0

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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  

Changes in the behavior of alginates, both non-gelled and gelled with calcium ions, in microcapsules after implantation in vivo were investigated using alginates enclosed in regenerated cellulose membrane. The mechanical properties of the alginates after soaking in simulated body fluid (SBF) and implantation in the peritoneal cavities of animals were determined. A stress-compression study on specimens soaked in SBF showed that the alginates in the microcapsules would have almost the same mechanical properties after several days of implantation independent of whether the enclosed alginate was non-gelled or gelled with calcium ions before implantation. The stresses at a particular compression point decreased with increasing incubation period for 3-6 days for the alginates gelled with calcium ions before soaking in SBR In contrast, these values increased over the same period for the non-gelled alginates before soaking in SBR In agreement with the results of the in vitro study, no significant differences were observed between the mechanical properties of the non-gelled and gelled alginates retrieved from the peritoneal cavities of DDY mice after 1 week of implantation. (C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.bej.2004.07.010

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Hydroxyapatite (HAp), the major inorganic component of hard tissues in vivo, was formed in/on a PVA gel. The HAp formation ratio depended on the reaction cycle number, but was independent of the alternate soaking period per cycle. The Ca/P molar ratio of HAp formed at 10 reaction cycles was very close to the theoretical value of HAp, 1.67. CHO-K1 cell adhesion, proliferation and maximum cell density on HAp plates were better on plates formed at two or five reaction cycles using 200 mM CaCl2 and 120 mM Na2HPO 4 solutions than on plates formed under other conditions. Furthermore, the adhesion ratio of CHO-K1 cells on HAp plates formed at 10 reaction cycles was about 60% of those at two or five reaction cycles. © 2003 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.bej.2003.07.004

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

The droplet breakup technique with an immiscible liquid coflowing stream was investigated for the preparation of mammalian cell-enclosing subsieve-sized capsules of less than 100 μm in diameter. The major parts of the droplet generation device were a needle of several hundred micrometers in diameter for extruding the cell-suspending sodium alginate aqueous solution and a tubule of 2.5 mm in diameter through which the extruded alginate solution flowed into ambient immiscible liquid paraffin. The needle was positioned upstream in the vicinity of the coaxial tubule. The droplet diameter of the viscous sodium alginate aqueous solution could be controlled from several dozen to several hundred micrometers by changing the velocities of the inner and ambient fluids and the diameter of the needle. By utilizing a 300-μm diameter needle, CHO-K1 cell-enclosing droplets of 48 ± 8 μm in diameter were obtained by extruding a cell-suspending sodium alginate solution at a velocity of 1.2 cm/sec into the ambient liquid paraffin flowing at a velocity of 23.5 cm/sec. The breakup process did not influence the viability of the enclosed cells, since more than 95% of the CHO-K1 cells remained alive after the enclosing process. © 2004 Wiley Periodicals, Inc.

DOI： 10.1002/bit.20006

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

A macroporous HAp culture substratum was formed by hydrothermal treatment of gypsum. The macropores derived from poly(methylmetacrylate) (PMMA) beads had diameters of 150-200 μm, and a porosity of 28% that was dependent on the PMMA beads quality. The maximum CHO-K1 cell density of the macroporous HAp microcarrier was 7.3 × 107 cells·m/-1-HAp. This value is similar to most existing suitable porous microcarriers. A macroporous HAp plate packed-bed type bioreactor was designed. The density of CHO-K1 cells in the bioreactor was seven times higher than that from a stationary culture. These results suggest that the HAp synthesized from gypsum by hydrothermal treatment is a suitable animal cell culture substratum. © 2004 The Society of Chemical Engineers, Japan.

DOI： 10.1252/jcej.37.531

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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 BV  

Mouse insulinoma (MIN6) cells were encapsulated into aminopropyl-silicate membrane deposited on calcium alginate gel beads via the sol-gel synthesis. Two alginates with different guluronic acid (G) contents, high and intermediate, but with the same molecular weights were used. Viability of the cells in the membrane templated by the alginate with an intermediate content of guluronic acid (intermediate-G) was approximately 10% higher than those in the membrane templated by the alginate with a high content of guluronic acid immediately after encapsulation. Growth of cells in vitro was hindered in case of encapsulation in the aminopropyl-silicate membrane deposited on the high-G alginate gel. The MIN6 cells in the-microcapsule made from high-G alginate needed a longer period to establish a normoglycemic in recipients than those in the microcapsule made from intermediate-G alginate despite the same number of viable cells implantation. Recipients of the microcapsule with the core made from the intermediate-G alginate maintained their blood glucose values less than 300 mg/dl for a longer period. (C) 2003 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.ijpharm.2003.10.014

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

In this study, a co-culture system of hepatocytes and bone marrow cells (BMCs) was developed and characterized for the expression and maintenance of ammonia metabolism and albumin secretion activities. A culture medium supplemented with epidermal growth factor, insulin, L-proline, hydrocortisone and 20 % (v/v) heat-inactivated fetal bovine serum was developed. In addition to adhesive bone marrow cells, the co-existence of non-adhesive bone marrow cells was effective in expressing liver-specific functions for at least 3 weeks. On the other hand, experiments with Transwell in which cultured cells were separated by a semi-permeable membrane, suggested that soluble factors secreted by BMCs are the key components in the functional enhancement of cells. Furthermore, direct contact between hepatocytes and BMCs enhanced the formation of spheroids and the expression of liver specific functions. These results indicate that this co-culture system is promising in, for example, bioartificial liver, regenerative medicine, and liver function simulator applications. © Wichtig Editore, 2004.

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記述言語：英語   出版者・発行元：公益社団法人 化学工学会  

We report a novel method to prepare nano scale vesicles with high encapsulation efficiency of target nucleotides. First, DNA was extracted from an aqueous solution into a cationic reverse micellar solution consisting of dimethyldistearylammonium bromide (2C18AB). Secondly, small amount of the reverse micellar solution containing DNA was dropped into an aqueous surfactant solution to form the outer-layer of vesicles. We mainly employed polyoxyethylene (20) sorbitan monolaurate (Tween 20) or cetyltrimethylammonium bromide (CTAB) as an outer-layer surfactant. Salt concentration of the aqueous solution affects the solubility of the organic solution droplets into the aqueous surfactant solution. At high NaCl concentration, over 60 % of extracted DNA was re-dispersed in the aqueous solution, while DNA was hardly dispersed in the solution without NaCl. Characterization of the resulting surfactant-DNA complexes was carried out by dynamic light scattering (DLS), and which showed that the average diameters were between 200-300 nm. This technique facilitates high encapsulation efficiency of DNA molecules into liposome, and the resultant lipid-DNA complex is nano-scale gene vector.

DOI： 10.11491/apcche.2004.0.478.0

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記述言語：英語   出版者・発行元：公益社団法人 化学工学会  

Hepatocyte transplantation using porous scaffolds is a potential therapy for both acute and chronic hepatic insufficiency and also for treatment of inborn errors of metabolism affecting liver. However, some authors reported that the hepatocytes located in the center of the scaffold died after transplantation due to insufficient oxygenation to the cells. No reports have been sufficiently addressed to resolve this problem. In this study, we fabricated a scaffold from poly (lacide acid) (PLA) coated with acidic gelatin. Basic fibroblast growth factor (bFGF) adsorbed onto the gelatin, would be released continuously and could induce angiogenesis in the scaffold in vivo. A combination of thickness and cell density in the scaffold was optimized so as to suppress the hepatocytes death in the center of the scaffold in the first stage of implantation. Further, a new centrifugal cell seeding method was developed to immobilize hepatocytes uniformly within the scaffold. The hepatocytes immobilized by the centrifugal cell seeding method in the bFGF-containing scaffold at the cell density optimized were implanted into mesentery of rat received a 70% hepatectomy. From observation of histological section of the scaffold after one week of implantation, it was confirmed that the living hepatocytes were uniformly distributed throughout the section, and exhibited PAS-positive indicating that they had a potential to store glycogen. This result indicates that the technique developed in this study was available for hepatocyte transplantation using a scaffold.

DOI： 10.11491/apcche.2004.0.480.0

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：KLUWER ACADEMIC PUBL  

Alginate/aminopropyl-silicate/alginate microcapsules, ca. 15 mum in membrane thickness and ca. 500 mum in diameter, were prepared via sol-gel process. The aminopropyl-silicate membrane was derived from two silicone alkoxide precursors, tetramethoxysilane and 3-aminopropyl-trimethoxysilane on Ca-alginate micro gel beads. Pancreatic beta-cell line (MIN6) cells were encapsulated in the microcapsule. The encapsulated MIN6 cells proliferated and formed spheroidal tissues in vitro. The diameter of the MIN6 spheroids increased to approximately 250 mum with an increase in the incubation period until the day 35. Storeptozotocin-induced diabetic mice became normoglycemia after implantation of the MIN6-enclosing microcapsules. The normoglycemic state remained until the retrieval of the implanted microcapsules for 1 month. These results indicate that the potential use of the alginate/aminopropyl-silicate/alginate microcapsule as a vehicle for a genetically engineered cell-enclosing therapeutic material delivery system.

DOI： 10.1023/A:1026045503586

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Proteases originating from Aspergillus melleus (Protease P) and Bacillus subtillis (Prolether FG-F) were entrapped into organic-inorganic hybrid silicates on Celite 545 by the sol-gel method, and their activities measured at 35° C for transesterification of chiral glycidol with vinyl n-butyrate in isooctane. n-Butyl- and dimethyl-substituted silicates provided 12.6 times higher activities with Protease P and 5.5 times with Prolether FG-F, respectively, than those deposited on Celite 545. Although pretreatment of those immobilized proteases with the chiral glycidol affected transesterification activities of both enantiomers, the ratio of the initial transesterification rate of (S)-(-)-glycidol to that of (R)-(+)-glycidol, remained unchanged.

DOI： 10.1080/1024242031000087628

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Biocompatibility and permeability of a microcapsule membrane governs the function of a microcapsule-shaped bioartificial pancreas. We have previously developed an alginate/sol-gel-synthesized aminopropyl-silicate/alginate microcapsule (Alg/AS/Alg), which had insufficient biocompatibility. The purpose of this study was to investigate whether the biocompatibility could improve by modifying the external surface with other anionic polymers and to investigate an influence of the modification on the permeability of the membrane. Four kinds of anionic polymers, poly(oxyethylene)diglycolic acid (3 kDa), heparin (15 kDa), Alg (54 kDa) and carboxymethylcellulose (CMC, 60 kDa) were used as the external anionic polymers. The heparin-bonded gel bead had the largest resistance to the diffusion of small molecules. The molecular mass cut-off point of 150 kDa required for immunoisolation was maintained for all anionic polymers. Cellular overgrowth to the implanted islet-enclosing microcapsule, a sign of insufficient biocompatibility, was suppressed by altering the external surface material from Alg to CMC. These results suggest that the biocompatibility of the Alg/AS/anionic polymer membrane can be improved by using a biocompatible anionic polymer. At the same time, it is suggested the influence on the permeability has to be investigated to develop an optimal microcapsule for bioartificial pancreas.

DOI： 10.1163/156856203322274905

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2003f.0.599.0

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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 BV  

An alginate/aminopropyl-silicate/alginate membrane was prepared on calcium-alginate gel beads via electrostatic interaction and sol-gel processes. The effects of the chemical composition and the molecular weight (MW) of the core alginate on the permeability of the alginate/aminopropyl-silicate/alginate membrane were investigated for five different types of alginates. Our data shows that an immunoisolatable MW cut-off point was achieved for the membranes formed on the alginates, MW = 7.0 x 10(4) with molar ratio of M/G (mannuronic acid to guluronic acid), M/G = 1.30, MW = 1.1 X 10(5) with M/G = 1.30, and MW = 7.0 x 10(4) with M/G = 0.65. For these three membranes, the membrane templated by the alginate of MW = 1.1 x 10(5) had a higher MW cut-off point than that templated by the alginate of MW = 7.0 x 10(4). In addition, the MW cut-off point increased with an increase in the content of guluronic acid. The membranes formed on the alginates of MW = 2.0 x 10(4) with M/G = 1.30, and MW = 7.0 x 10(4) with M/G = 2.25 did not have an immumoisolatable MW cut-off point. (C) 2002 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0376-7388(02)00093-5

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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 BV  

A novel microcapsule membrane composed of aminopropyl-silicate was synthesized on Ca-alginate gel beads from 3-aminopropyltrimethoxysilane (APTrMOS) and tetramethoxysilane (TMOS) by the sol-gel method. Preparation conditions such as the molar ratio of APTrMOS to TMOS, the sequence of addition and the contact time of each precursor were examined to give the membrane immunoisolatable permeability for microcapsule-shaped bioartificial organs. The permeability of the membrane decreased with an increase of up to 2.4 in the molar ratio, with gamma-globulin being completely rejected at this ratio. Addition of APTrMOS prior to TMOS and allowing 1 min of contact with the Ca-alginate gel beads suspended in n-hexane was effective for rejection of gamma-globulin. The optimized aminopropyl-silicate membrane was estimated to give a molecular weight cut-off point of less than 150 kDa, as required for immunoisolation, and an excellent permeability to low molecular weight substances such as glucose and oxygen. Our data show that the permeability of the aminopropyl-silicate membrane, that is the microscopic structure of the membrane, is strongly controllable by altering preparation conditions. (C) 2002 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0376-7388(01)00731-1

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The aminopropyl-silicate-titanate hybrid membrane was successfully synthesized onto a Ca-alginate gel bead by the sol-gel method, from two kinds of organometallic compound precursors, tetraethyl orthotitanate (TEOTi) [Ti(OC2H5)4] and 3-aminopropyltrimethyl orthosilicate (APTrMOS) [(CH3O)3Si(CH2)3NH2]. APTrMOS acted as a binding agent between inorganic titanate and alginate polymer via electrostatic interaction between amino groups of APTrMOS and carboxyl groups of alginate. From the measurements of the diffusion of ovalbumin and γ-globulin through the aminopropyl-silicate-titanate hybrid membrane, it was found that the molecular permeability of the membrane could be controlled by changing the amount of each precursor. The molecular weight cutoff point required for immunoisolation, less than 150kDa, was achieved under the condition that the amount of APTrMOS was 3.40 mmol/ (10 ml of Ca-alginate) and TEOTi was more than 1.42 mmol. The islets encapsulated in the membrane showed almost the same insulin secretion viability as the free islets.

DOI： 10.1007/s100470200009

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

To prepare an immobilized lipase effective for enantioselective esterification of glycidol with n-butyric acid in organic media, hybrid gel-entrapped lipase on Celite was prepared by the sol-gel method and pretreated with chiral template substrates. When n-butyltrimethoxysilane, (n-BuTrMOS) as an organic silane precursor, was mixed with tetramethoxysilane (TMOS) at a molar ratio of 4:1, the hybrid gel-entrapped lipase on Celite showed three times higher activity than the deposited lipase on Celite as a control. The pretreatment of this immobilized lipase with a hydrophobic enantiomer such as (R)-(-)-2-octanol brought about a selective enhancement of the activity for the esterification of (R)-(+)-glycidol, whereas such pretreatment hardly affected the activity for the esterification of (S)-(-)-glycidol. Consequently, the relative initial enantiomeric activity (RIEA) of the hybrid gel-entrapped lipase on Celite, defined as a ratio of the initial esterification rate of (R)-(+)-glycidol to that of (S)-(-)-glycidol, changed between 0.76 and 2.0. In addition, increasing the concentration of (R)-(-)-2-octanol as a template substrate, increased the activity and RIEA, and showed maximum values with the addition of 21mM of (R)-(-)-2-octanol. Copyright © 2002 Elsevier Science B.V.

DOI： 10.1016/S1381-1177(01)00076-5

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：KLUWER ACADEMIC PUBL  

To prepare an immobilized protease with a high activity for transesterification of vinyl n-butyrate with 3-methyl-1-butanol (isoamyl alcohol) in organic media, a protease was entrapped into organic-inorganic hybrid silica gel on Celite 545 by the sol-gel method. When propyltrimethoxysilane was used as the organic silane precursor mixed with tetramethoxysilane at a molar ratio of 16:1, the hybrid gel-entrapped protease on Celite 545 had 8 times the activity of the protease deposited on Celite 545 from 35 to 85 degreesC.

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Alginate/aminopropyl-silicate/alginate (Alg/AS/Alg) membrane was prepared on Ca-alginate gel beads by a sol-gel process. The membrane has ≡Si-O-Si≡ bonds as well as electrostatic bonds between amino groups of AS and carboxyl groups of alginate. Permeability and stability were investigated for the membrane. Furthermore, rat islets encapsulated in the membrane (499±32μm in diameter, 1000 islets/recipient) were transplanted to the peritoneal cavities of the mice with streptozotocin-induced diabetes. Our data show that the membrane had the molecular weight cut-off point of between 70 and 150kDa, and hardly inhibited the permeation of glucose and insulin. The Alg/AS/Alg microcapsule was more stable than the well-known Alg/poly-L-lysine (PLL)/Alg microcapsule. After 30 days of soaking in stimulated body fluid, the percentages of intact microcapsule were 98.4±0.5 (mean±SEM)% and 88.0±1.5% (p&lt
0.001) for the Alg/AS/Alg and Alg/PLL/Alg microcapsules, respectively. The maximum maintenance period of normoglycemia was 105 days without administration of immunosuppressive drugs. Copyright © 2002 Elsevier Science Ltd.

DOI： 10.1016/S0142-9612(02)00159-X

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

We utilized the sol-gel reaction to prepare an immunoisolatable membrane for a microcapsule-shaped bioartificial pancreas. The membrane, derived from two precursors, 3-(aminopropyl)trimethoxysilane (APTrMOS) and tetramethoxysilane (TMOS), was formed onto calcium-alginate gel beads via electrostatic interaction. The molecular weight cutoff point of less than 150 000 required for immunoisolation was achieved at molar ratios ([APTrMOS]/[TMOS]) ranging from 0.60 to 2.40 with the amount of APTrMOS fixed at 3.40 mmol/(10 mL of calcium-alginate). When encapsulated in a membrane prepared at the molar ratio of 0.60, the islets contracted in volume and showed no response to stimulation by a high glucose concentration. However, islets in a membrane prepared at the molar ratio of 2.40 showed no contraction and responded to the glucose stimulation at almost the same level as free islets. These results demonstrated that the molar ratio of the precursors was a dominant factor affecting membrane permeability and the insulin secretion activity of the encapsulated islets.

DOI： 10.1021/bp010147+

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In order to develop a microcapsule-shaped bioartificial pancreas, it is important to control the transport characteristics of the semipermeable membrane. We attempt to control the transport characteristics of the membrane by changing the coating layer number of polyelectrolyte complex between glycol chitosan (GC, M. W.&gt;8.2×10 4) and alginate (Alg) on the microcapsule. From measurement of diffusivities of bovine serum albumin (BSA, M. W.=6.7×10 4) and γ-globulin (M. W. = 1.6×10 5), these diffusion rates through the membrane drastically decrease with increasing layer number of GC-Alg. The microcapsule coated with four layers of polyelectrolyte complex successfully rejects γ-globulin with effective permeability of BSA. In addition, the diffusivity of glucose (M. W.=180) indicateds that the multi-layering of polyelectrolyte complex hardly affects the diffusivity of small substances such as nutrients and oxygen. These results indicate that the polyelectrolyte complex prepared by the multilayering method is useful to control the transport characteristic of membranes and the four-layered GC -Alg polyelectrolyte complex microcapsule is promising for a microcapsule-shaped bioartificial pancreas.

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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 SCI LTD  

To develop a novel type of immunoisolation membrane for a microcapsule-shaped bioartificial pancreas, we attempted to use a sol-gel synthesized silicate. An aminopropyl-silicate membrane derived from 3-aminopropyltrimethoxysilane and tetramethoxysilane was formed on Ca-alginate gel beads via electrostatic interaction. The positively charged amino groups remaining on the surface of the resultant gel beads were neutralized by immersion in an aqueous Na-alginate solution. From measurements of the partition coefficients and effective diffusivities of different substances to the gel beads, it was found that the aminopropyl-silicate membrane prepared under optimized composition of silicon alkoxide precursors successfully rejected gamma -globulin, giving good permeability to substances having a low molecular weight. Islets could be encapsulated within the newly developed microcapsules while retaining their ability to secrete insulin. (C) 2001 Elsevier Science Ltd. All rights reserved.

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

By performing pretreatment with substrate analogues, an activation of lipase immobilized into organic-inorganic hybrid silicate was attempted in esterification of menthol with butyric acid in organic media. With decreasing water content of immobilized lipase preparations, the activity of immobilized lipases by (-)-menthol pretreatment was enhanced, and the highest activity was obtained at water activity, aw=0.11. However, the pretreatment of immobilized lipases with (-)-menthol could not improve the enantioselectivity. In addition, the activity of pretreated immobilized lipases increased with increasing the chain length of alcohol as a substrate analogue. Consequently, it was found that hydrophobic and bulky alcohol was an effective substrate analogue to activate immobilized lipases. Copyright © 2001 Elsevier Science B.V.

DOI： 10.1016/S1381-1177(01)00007-8

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：New York Academy of Sciences  

To evaluate the performance of an artificial liver, we created a recoverable hepatic failure rat model. This involves a 30-60 minute warm ischemia, via clamping, of one-third of the liver with a partial (two-thirds) hepatectomy. Variations on this method provide for the possibility of several modes of hepatic failure. Survival time of the rats was prolonged (35%) by applying our hybrid artificial liver. However, the extracorporeal circulation is a considerable burden to the rat. Therefore, we need to apply the hybrid artificial liver intermittently and repeatedly.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：NEW YORK ACAD SCIENCES  

An aminopropyl-silicate membrane, synthesized from tetramethoxysilane (TMOS) and 3-aminopropyltrimethoxysilane (APTrMOS) by the sol-gel method, was formed onto Ca-alginate gel beads via electrostatic interactions. The permeability of the membrane could be controlled easily by changing the molar ratio of both the precursors ([APTrMOS]/[TMOS]). The aminopropyl-silicate membrane prepared at a molar ratio of 2.40 rejected gamma-globulin and BSA successfully, whereas it permeated ovalbumin. This result indicates that the molecular weight cutoff point of this newly developed aminopropyl-silicate membrane is approximately 60 kDa.

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担当区分：最終著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（商業誌、新聞、ウェブメディア）  

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記述言語：日本語   出版者・発行元：電子情報通信学会  

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記述言語：日本語   出版者・発行元：Institute of Electrical Engineers of Japan  

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記述言語：日本語   出版者・発行元：Institute of Electrical Engineers of Japan  

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担当区分：筆頭著者   記述言語：日本語   出版者・発行元：化学工学会  

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担当区分：最終著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

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記述言語：日本語  

DOI： 10.11522/pscjspe.2011S.0.941.0

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DOI： 10.11522/pscjspe.2010S.0.475.0

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記述言語：英語   出版者・発行元：超音波エレクトロニクスの基礎と応用に関するシンポジウム運営委員会  

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記述言語：日本語  

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記述言語：日本語   出版者・発行元：日本生物工学会  

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2008f.0.643.0

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In order to investigate the effect of pressure on the tertiary structure of plasmid DNA having the supercoiled and relaxed forms, the solution of plasmid DNA was hydrostatically pressurized at different atmosphere and 40 degrees C for various times. For dynamic light scattering (DLS) measurement of the pressurized plasmid DNA, the hydrodynamic diameters of the super-coiled and relaxed plasmid DNA were decreased with increasing pressure. Also, at constant pressure, a long period of pressure treatment effectively induced the decrease in plasmid DNA. These results suggest that the plasmid DNA was condensed by high hydrostatic pressurization. The circular dichroism (CD) spectrum of the pressurized plasmid DNA was slightly changed. For digestion by S1 nuclease, which selectively cleaves single strand DNA, the pressurized plasmid DNA was easily degraded compared to the non-pressurized plasmid DNA, suggesting that the double helix of plasmid DNA was partly dissociated to single strand by the pressure-induced compaction of plasmid DNA. These results indicate that high hydrostatic pressurization is one of powerful tools for preparing the compacted plasmid DNA.

DOI： 10.1093/nass/nrm172

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Micro-bioreactors are effective for high throughput production of expensive products from small amounts of substrates. Lipases are versatile enzymes for chiral syntheses, and highly activated when immobilized in alkyl-substituted silicates by the sol-gel method. For application of the immobilized lipases to a continuous-flow system, a micro-bioreactor loaded with a macroporous silica monolith is well suited, because it can easily be integrated with a separator for optical resolution. We attempted to develop a micro-capillary bioreactor containing a silica monolith-immobilized lipase. A silica monolith without shrinkage during lyophilization of the hydrogel was first formed from a 1:4 mixture of tetramethoxysilane (TMOS) and methyltrimethoxysilane (MTMS). It was then coated with silica precipitates entrapping lipase, derived from a 1:4 mixture of TMOS and n-butyltrimethoxysilane (BTMS). As a result, the monolith treated with the BTMS-based silica entrapping lipase, exhibited approximately ten times higher esterification activity than the non-treated monolith-immobilized lipase derived from the MTMS-based silica.

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記述言語：日本語   出版者・発行元：化学工業社  

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記述言語：英語  

Solubilization of horse heart cytochrome c into reverse micelles, a self-assembled nanostructure composed of sodium di-2-ethylhexyl sulfosuccinate (AOT), enhances the peroxidase activity in the presence of hydrogen peroxide. The catalytic activity of cytochrome c hosted in reverse micellar solution is 10-fold higher than that in water, and which depends on Wo, a molar ratio of water to AOT, and pH in aqueous droplets. In addition, the fluorescence intensity based on the tryptophan residue and the visible absorption identifying the axial Met 80-Fe bond imply that the reverse micellar solubilization induces the cleavage of the heme crevice and thus enables the formation of peroxidase-like peroxide-heme complexes. These results suggest that cytochrome c solubilized in reverse micelles provides a homogeneous catalyst as peroxidase available in organic media. © 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.bej.2005.10.005

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記述言語：日本語   出版者・発行元：日本生物工学会  

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記述言語：英語   掲載種別：研究発表ペーパー・要旨（国際会議）   出版者・発行元：ELSEVIER SCIENCE BV  

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記述言語：日本語   出版者・発行元：日本生物工学会  

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その他リンク： http://search.jamas.or.jp/link/ui/2006284342

A method for preparing monodisperse mammalian cell-enclosing subsieve-sized microcapsules from viscous polymer solution was developed. The droplet breakup technique with an immiscible liquid coflowing stream was applied for the preparation of subsieve-sized mammalian cell-enclosing capsules. The reaction was found to enhance cell viability due to reduced resistance to the transport of oxygen, nutrients and metabolites. Mechanical strength and biocompatibility were also found to be enhanced.

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記述言語：英語  

Deoxyribonucleotide (DNA) was successfully extracted in a few hours by reverse micelles, which were formed and functionalized by a cationic quaternary ammonium surfactant in isooctane. Several parameters which affect the DNA transfer from an aqueous phase to a reverse micellar phase, such as the natures of a surfactant and a solvent, salt concentration in a feed solution, and hydrophobicity of micelles, were investigated. The use of a cationic surfactant was found to yield a high transfer rate of DNA into reverse micelles. We have attributed the DNA transfer to the electrostatic interaction between the cationic surfactant and the negatively charged DNA. We found that the higher the hydrophobicity of a surfactant used to form micelles, the better the DNA transfer efficiency in the forward extraction. Preferential extraction of DNA was achieved by using twin long-alkyl chains of cationic surfactants. However, pH in the aqueous feed solution did not affect the extraction performance of reverse micelles. On the other hand, alcohol, as a co-solvent plays an important role in the back extraction of DNAs. Complete back-extraction of DNAs was achieved without any conformational change by adding an appropriate alcohol to the reverse micellar phase. © 2004 The Society of Chemical Engineers, Japan.

DOI： 10.1252/jcej.37.662

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記述言語：日本語   出版者・発行元：日本生物工学会  

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記述言語：日本語   出版者・発行元：日本生物工学会  

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記述言語：日本語   出版者・発行元：日本生物工学会  

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記述言語：日本語   出版者・発行元：日本生物工学会  

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その他リンク： http://search.jamas.or.jp/link/ui/2006231271

記述言語：日本語   出版者・発行元：日本生物工学会  

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その他リンク： http://search.jamas.or.jp/link/ui/2006231268

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記述言語：日本語   出版者・発行元：日本生物工学会  

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その他リンク： http://search.jamas.or.jp/link/ui/2003139673

記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Cytochrome c solubilized in reversed micelles formulated with di-2-ethylhexyl sulfosuccinate (AOT) has allowed to catalyze the oxidation of o-phenylenediamine (o-PDA) with hydrogen peroxide. The oxidative reaction did not occur effectively by cytochrome c in water. The nanostructural environment in reversed micelles seemed to perturb the three-dimensional structure of the active site of cytochrome c. The product obtained in reversed micelles had a specific absorption spectrum with the absorption peak at 720 nm, indicating a blue-colored solution, whereas common peroxidases such as horseradish peroxidase provided a yellow-colored product in water with the absorption peak at 420 nm. The difference in the oxidative products suggests that AOT molecules play an important role in the specificity of o-PDA oxidation. The dependency of the product species on the pH of the inner droplet in reversed micelles indicated that the specific oxidative product was prepared by electrostatic interaction with AOT molecules. (C) 2001 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S1381-1177(00)00173-9

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記述言語：英語  

Extraction behavior of active and denatured α-chymotrypsin is investigated by the reversed micellar extraction technique. The anionic surfactant dioleyl phosphoric acid (DOLPA) selectively extracted the active protein over the denatured protein. However, the reversed micelles using AOT do not afford selectivity. Based on the difference in the structural properties between the active and the heated α-chymotrypsin, the extraction behavior by the DOLPA reversed micelles is discussed. Key words: extraction, reverse micelle, surfactant, protein separation, AOT. © 2001, The Society of Chemical Engineers, Japan. All rights reserved.

DOI： 10.1252/kakoronbunshu.27.181

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記述言語：日本語   出版者・発行元：日本生物工学会  

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記述言語：日本語   出版者・発行元：日本生物工学会  

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Refolding of denatured RNase A as a model of inclusion bodies was performed by reversed micelles formulated with sodium di-2-ethylhexyl sulfosuccinate (AOT) in isooctane. In the novel refolding process, a solid-liquid extraction was utilized as an alternative to the ordinary protein extraction by reversed micelles based on a liquid-liquid extraction. First, the effects of operational parameters such as concentration of AOT, W-o (= [H2O]/[AOT]), and pH were examined on the solubilization of solid denatured proteins into a reversed micellar solution. The solubilization was facilitated by a high AOT concentration, a high W-o value, and a high pH in water pools. These conditions are favorable for the dispersion of the solid protein aggregates in an organic solvent. Second, the renaturation of the denatured RNase A solubilized into the reversed micellar solution was conducted by addition of glutathione as a redox reagent. A complete renaturation of RNase A was accomplished by adjusting the composition of the redox reagent even at a high protein concentration in which protein aggregation would usually occur in aqueous media. In addition, the renaturation rates were improved by optimizing water content (W-o) and the pH of water pools in reversed micelles. Finally, the recovery of renatured RNase A from the reversed micellar solution was performed by adding a polar organic solvent such as acetone into the reversed micellar solution. This precipitation method was effective for recovering proteins from reversed micellar media without any significant reduction in enzymatic activity.

DOI： 10.1021/bp000073m

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記述言語：日本語   出版者・発行元：SOC CHEMICAL ENG JAPAN  

The capabilities of Candida rugosa lipase, which was immobilized into organically modified silicates formed on kieselguhr such as Celite 545 are investigated in esterification of (-)- or (+)-menthol with butyric acid. In this study, we optimized the preparation conditions such as a molar ratio of precursors. From these investigations, we find that the optimized hybrid gel-immobilized lipase is derived from a mixture of dimethyldimethoxysilane and tetramethoxysilane at a molar ratio of 4 : 1 and its enantioselectivity, which is defined as a ratio of the initial reaction rate of (-)-menthol to that of (+) -menthol, is enhanced up to 41 at 75 degreesC. In addition, we observe the temperature dependence of these immobilized lipases. Consequently, the optimized hybrid gel-immobilized lipase shows higher activity than deposited lipase on Celite at all temperatures, and it is suggested that this activation results from a remarkable enhancement of the V-max value.

DOI： 10.1252/kakoronbunshu.26.882

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記述言語：英語   出版者・発行元：TAYLOR & FRANCIS LTD  

Glycol chitosan is a positively charged polysaccharide which is water-soluble at pH 7.4, and is able to form a polyion complex (PIC) with anionic polymers, such as alginate. The authors attempt to develop a novel type of alginate-based microcapsule using this glycol chitosan for a islets-encapsulated bioartificial pancreas. The number of layers composed of glycol chitosan-alginate (GC-Alg) PIC were optimized, in order to cut off immunoglobulin transport and to protect encapsulated islets from the host immune reaction, and the transport characteristics were evaluated of glucose, bovine serum albumin (BSA) and gamma-globulin. To add mechanical stability to the microcapsule, calcium ions, which crosslinked the alginate polymers close to the interface between core Ca-alginate and multilayered membrane, were partially substituted with barium ions after the formation of multilayered Ca-alginate gel beads. The partition coefficients of BSA and gamma-globulin were decreased with the increasing number of layers. The immunoisolation was achieved against gamma-globulin with four layers of the GC-Alg PIC membrane, while BSA could permate the membrane. The foul-layered Ba-alginate gel bead had a good permeability for glucose, giving a diffusion coefficient corresponding to 80% of that in pure water. Insulin secretion from the islets in the four-layered Ba-alginate microcapsule was satisfactorily observed with the fractional stimulation ratio of 2.17. This result indicates that the encapsulated islets maintained their viability even after encapsulation. It was, thus, shown that the Ba-alginate microcapsule with four layers of the GC-Alg PIC membrane is promising as the microencapsulation material for a bioartificial pancreas.

DOI： 10.1080/02652040050161684

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記述言語：日本語   出版者・発行元：THE MEMBRANE SOCIETY OF JAPAN  

Reversed micelles, which are nanostructural molecular assemblies formed by surfactant molecules in an organic solvent, are a promising separation tool for biomolecules such as amino acids, proteins and nucleic acids. In the separation by reversed micelles, biomolecules transfer from an aqueous solution into a reversed micellar phase through the interaction between surfactant molecules and a target biomolecule : e.g. electrostatic interaction, hydrophobic interaction, hydrogen bonding and/or affinity interaction. In particular, the electrostatic interaction has been found to play an important role in the degree of extraction, and the design of reversed micelles often decides the success of separation efficiency. In this article, we reviewed the recent investigation concerning the reversed micellar extraction techniques for biomolecules ; mainly proteins and deoxyribonucleic acids (DNAs). We also describe the transfer mechanism of proteins through the protein-surfactant complexes at the liquid-liquid interface. DNAs were first demonstrated to be transferred from an aqueous solution to the reversed micellar phase by using a cationic surfactant. Furthermore, we introduce recent novel application of reversed micelles to the separation of biomolecules.

DOI： 10.5360/membrane.25.23

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00087896763?from=CiNii

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DOI： 10.1252/kakoronbunshu.26.882

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記述言語：日本語   出版者・発行元：広信社  

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記述言語：英語   出版者・発行元：Society of Chemical Engineers, Japan  

Deoxyribonucleotide (DNA) from salmon testes was successfully extracted by reversed micelles that are formed by a cationic surfactant in isooctane. The degree of extraction of DNA was strongly influenced by the type of surfactant in the organic solvent and ionic strength in the material aqueous phase. The driving force of the DNA transfer was electrostatic interaction between cationic surfactants and negatively charged DNA. Cationic surfactants possessing two long-alkyl chains are one of the best candidates for the successful transfer of DNA from an aqueous solution to a reversed micellar solution. Copyright © 1999 The Society of Chemical Engineers,.

DOI： 10.1252/jcej.32.123

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記述言語：日本語   出版者・発行元：日本生物工学会  

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

The extraction mechanism of proteins by surfactant molecules in an organic solvent has been investigated using a chemically modified protein. We conducted guanidylation on lysine residues of cytochrome c by replacing their amino groups with homoarginine to enhance the protein-surfactant interaction. Results have shown that guanidylated cytochrome c readily forms a hydrophobic complex with dioleyl phosphoric acid (DOLPA) through hydrogen bonding between the phosphate moiety and the guanidinium groups. Although improved protein-surfactant interaction activated the formation of a hydrophobic complex at the interface, it could not improve the protein transfer in isooctane. It has been established that the protein extraction mechanism using surfactant molecules is mainly governed by two processes: formation of an interfacial complex at the oil-water interface and the subsequent solubilization of the complex into the organic phase. In addition, a kinetic study demonstrated that guanidylation of lysine accelerated the initial extraction rate of cytochrome c. This fact implies that the protein transferability from aqueous phase into organic phase depends on the protein-surfactant interaction which can be modified by protein surface engineering.

DOI： 10.1021/bp9800844

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記述言語：英語   出版者・発行元：AIChE  

Novel reversed micellar solutions formulated with a mixture of AOT (dioctyl sulfosuccinate) and DOLPA (dioleyl phosphoric acid) show good potential for use in reversed micellar protein extraction operations. Chymotrypsin is easily extracted from an aqueous phase into organic isooctane containing 10 mM AOT and DOLPA in a 4:1 ratio. The extraction ability of the mixed reversed micelles of 10 mM was higher than that of 200 mM AOT alone. The results of extraction indicated that the AOT-DOLPA mixed reversed micelles are very useful for separating and enriching chymotrypsin. Back-extraction of chymotrypsin from the organic phase to a fresh aqueous phase is also accomplished by adding an alcohol to the organic phase. Although the backtransfer of chymotrypsin from the reversed micelles formed by AOT alone is very slow and difficult, in the AOT-DOLPA mixed reversed micelles, the back-extraction can be achieved completely by addition of 10% (v/v) isobutyl alcohol to the reversed micellar phase. The time to attain to the equilibrium of back-extraction was reduced from more than 24 to 2 h by adding the alcohol. On the basis of the activity data, the best composition of AOT and DOLPA was a 4:1 ratio and the total surfactant concentration was 10 mM. The activity of chymotrypsin recovered from the mixed reversed micelles was higher than that of the initial protein before the forward-transfer. This result means that the novel mixed reversed micellar solutions are useful not only in separation but also in purification of proteins.

DOI： 10.1021/bp9800790

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記述言語：英語   出版者・発行元：JOHN WILEY & SONS INC  

This article reports that a reversed micellar solution is useful for refolding proteins directly from a solid source. The solubilization of denatured RNase A, which had been prepared by reprecipitation from the denaturant protein solution, into reversed micelles formulated with sodium di-2-ethylhexyl sulfosuccinate (AOT) has been investigated by a solid-liquid extraction system. This method is an alternative to the ordinary protein extraction in reversed micelles based on the liquid-liquid extraction. The solid-liquid extraction method was found to facilitate the solubilization of denatured proteins more efficiently in the reversed micellar media than the ordinary phase transfer method of liquid extraction. The refolding of denatured RNase A entrapped in reversed micelles was attained by adding a redox reagent (reduced and oxidized glutathion). Enzymatic activity of RNase A was gradually recovered with time in the reversed micelles. The denatured RNase A was completely refolded within 30 h. In addition, the efficiency of protein refolding was enhanced when reversed micelles were applied to denatured RNase A containing a higher protein concentration that, in the case of aqueous media, would lead to protein aggregation. The solid-liquid extraction technique using reversed micelles affords better scale-up advantages in the direct refolding process of insoluble protein aggregates. (C) 1998 John Wiley & Sons, Inc.

DOI： 10.1002/(SICI)1097-0290(19980305)57:5<620::AID-BIT14>3.0.CO;2-F

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記述言語：英語  

Novel reversed micelles formulated by sodium dioleylphosphate (SDOLP) has been developed for enzymatic reaction in organic media. Comparison study between sodium bis-(2-ethylhexyl)-sulfosuccinate (Aerosol-OT or AOT) and SDOLP, which was carried out by investigating the reactivity of each reversed micellar system as reaction media for enzymatic transesterification reaction of N-acetyl-1-phenylalanine ethyl ester (APEE) and 1-propanol, leads to the upshot that α-chymotrypsin immobilized within SDOLP reversed micelles can persevere its high catalytic activity in isooctane. The initial reaction rate of the SDOLP reversed micellar system is almost 60 times higher than that in the AOT system. Additional kinetic results, including the Michaelis constant and the maximum reaction rate, reveal that the inner core of the SDOLP reversed micelles provides a better environment for enzymatic reaction than that of the conventional AOT reversed micelles. © 1998 Elsevier Science S.A. All rights reserved.

DOI： 10.1016/S1369-703X(98)00013-8

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記述言語：英語   掲載種別：書評論文，書評，文献紹介等   出版者・発行元：CURRENT SCIENCE LTD  

Reverse micelles have found wider biological applications recently in terms of providing an enabling hydrophilic environment for solubilized functional biomaterials in organic media. Further, separation and purification of target proteins from aqueous solution using micellar aggregates created in hydrophobic media as well as efficient refolding of proteins in micellar solutions have become possible.

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記述言語：英語   出版者・発行元：John Wiley &amp; Sons Inc  

New surfactants have been synthesized for potential use in reversed micellar protein extraction operations. Preferential solubility of the surfactant in an aliphatic solvent such as hexane, heptane, or isooctane and the formation of reversed micelles accompanied with solubilization of significant quantities of water can be achieved by using strongly hydrophobic, twin alkyl chains as the hydrophobic moiety. Different surfactants having identical water-solubilizing capacities can have significantly different behavior in protein extractions, where extraction efficiency appears to be governed by the nature of the interfacial complex that forms between surfactants and proteins. Bulky surfactant chains provide a steric hindrance to the adsorption of the surfactant to the protein surface, thus inhibiting solvation of the protein/surfactant complex, and hence protein extraction. Under these conditions, a precipitate forms either in the bulk aqueous phase or at the interface. Surfactants that can form a close-packed complex with the protein are excellent protein-solubilizing agents. Dioleyl phosphoric acid (DOLPA) appears to be the best surfactant currently available for protein extraction.

DOI： 10.1002/(SICI)1097-0290(19970405)54:1<26::AID-BIT3>3.0.CO;2-#

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記述言語：日本語   出版者・発行元：分離技術会  

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The effect of organic solvents on the extraction behaviour of cytochrome c has been investigated with reversed micellar solutions. An aliphatic solvent such as hexane, octane or isooctane was suitable for protein extraction operations using the reversed micelles. Organic solvents having a different hydrophobicity show significantly different behaviour in protein extraction, where extraction efficiency appears to be governed by the nature of the interfacial complex that is formed by surfactants and proteins. Solvent effects on the protein extraction are more dominant in the AOT system rather than that in the DOLPA system. Addition of alcohol appears to decrease the activity of proteins in the back-extraction step, although it is effective for recovering proteins from the reversed micellar solutions.

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

A new surfactant, dioleyl phosphoric acid (DOLPA), has been applied to the extraction of hemoglobin using reversed micelles. The reversed micelles formed by DOLPA can easily extract hemoglobin from aqueous to reversed micellar solutions. DOLPA is the first surfactant to extract hemoglobin completely without using any cosurfactants. On the basis of the difference between DOLPA and AOT reversed micelles in the forward extraction behavior of hemoglobin, the nature of the interfacial complex that would be formed between surfactants and hemoglobin at the oil-water interface was found to be the dominant factor in determining the extraction efficiency of hemoglobin by reversed micelles. In addition, back-transfer studies of hemoglobin from the DOLPA reversed micelles were also carried out by the phase transfer method. It was found that hemoglobin, once dissolved into the DOLPA reversed micelles, is not transferred to a fresh aqueous solution even when the conditions are adjusted to not allow the forward transfer of hemoglobin. However, the addition of several kinds of alcohol drastically improved the yield in the back-transfer of hemoglobin. The efficiency in the back-transfer of hemoglobin strongly depends on the aqueous conditions that are in contact with the reversed micelles, such as pH, ionic strength, and alcohol concentration. A pH higher than the pi of hemoglobin, a salt concentration lower than that of the water pool, and the proper concentration of alcohol are required for the recovery aqueous phase to ensure the back-transfer of hemoglobin from the DOLPA reversed micelles.

DOI： 10.1021/bp960055y

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記述言語：英語   出版者・発行元：SOC CHEMICAL ENG JAPAN  

DOI： 10.1252/jcej.29.695

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記述言語：英語   出版者・発行元：Springer Netherlands  

The extraction behavior of native and heated-denatured α-chymotrypsin has been investigated with two different reversed micellar systems. A large difference in the degree of extraction was observed for the native relative to the denatured α-chymotrypsin. In particular, mixed reversed micelles formulated with DOLPA (dioleyl phosphoric acid) and AOT show a high selectivity for the active α-chymotrypsin.

DOI： 10.1007/BF00158935

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記述言語：英語  

Di(tridecyl) phosphoric acid (DTDPA) was synthesized as a new surfactant for protein extraction by reversed micelles. DTDPA can form stable reversed micelles in the concentration range above 1 mM. The size of the DTDPA reversed micelles was smaller than that of conventional AOT (sodium-di-2-ethylhexyl sulfosucci-nate) reversed micelles under the same conditions. The formation of reversed micelles using DTDPA can be controlled by adjusting the aqueous pH. The extraction behavior of some proteins from an aqueous phase into the reversed micellar phase of DTDPA has been investigated by varying the experimental conditions (pH, ionic strength, surfactant concentration). It was found that reversed micelles with DTDPA can extract many proteins. In particular, hemoglobin, which is difficult to extract with an AOT reversed micelle, can be extracted in the DTDPA reversed micelles. In the new reversed micellar system, phase separation was very fast even at a high concentration of DTDPA. © 1995, Taylor &amp
Francis Group, LLC. All rights reserved.

DOI： 10.1080/01496399508012215

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記述言語：日本語   出版者・発行元：広信社  

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記述言語：日本語   会議種別：シンポジウム・ワークショップ パネル（指名）  

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出願人：岡山大学

出願番号：特願2010-147437  出願日：2010年6月29日

公開番号：特開2012-011268  公開日：2012年1月19日

特許番号/登録番号：特許第5780507号  登録日：2015年7月24日 

権利者：岡山大学

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出願人：岡山大学

出願番号：特願2010-147438  出願日：2010年6月29日

公開番号：特開2012-011269 

特許番号/登録番号：特許第5858451号  登録日：2015年12月25日  発行日：2016年2月10日

権利者：岡山大学

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出願人：国立大学法人岡山大学

出願番号：特願2019-164247 

特許番号/登録番号：特許7376072号  登録日：2023年10月30日  発行日：2023年10月30日

権利者：国立大学法人岡山大学

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種別：展覧会 

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種別：学会・研究会等 

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種別：学会・研究会等 

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