2024/11/26 更新

写真a

カワムラ アキフミ
河村 暁文
KAWAMURA,Akifumi
所属
化学生命工学部 教授
職名
教授
外部リンク

学位

  • 博士(工学) ( 2008年3月   大阪府立大学 )

研究分野

  • ナノテク・材料 / 高分子化学

  • ナノテク・材料 / 高分子材料

  • 環境・農学 / 環境材料、リサイクル技術

  • ライフサイエンス / 生体材料学

学歴

  • 大阪府立大学   大学院工学研究科   物質・化学系専攻 応用化学分野

    2005年4月 - 2008年3月

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    国名: 日本国

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  • 大阪府立大学   大学院工学研究科   物質系専攻 機能物質化学分野

    2003年4月 - 2005年3月

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    国名: 日本国

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  • 大阪府立大学   工学部   応用化学科

    1999年4月 - 2003年3月

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    国名: 日本国

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経歴

  • 関西大学   化学生命工学部 化学・物質工学科   教授

    2024年4月 - 現在

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    国名:日本国

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  • マサチューセッツ州立大学アマースト校   Polymer Science and Engineering Department   客員研究員

    2018年9月 - 2019年9月

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  • 関西大学   化学生命工学部 化学・物質工学科   准教授

    2017年4月 - 2024年3月

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    国名:日本国

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  • 関西大学   化学生命工学部 化学・物質工学科   助教

    2012年4月 - 2017年3月

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    国名:日本国

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  • 関西大学   先端科学技術推進機構   ポストドクトラルフェロー

    2011年3月 - 2012年3月

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    国名:日本国

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  • 東レ株式会社   先端融合研究所

    2008年4月 - 2011年2月

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    国名:日本国

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▼全件表示

所属学協会

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委員歴

  • 公益社団法人 高分子学会   高分子ゲル研究会運営委員  

    2024年4月 - 現在   

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    団体区分:学協会

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  • 日本化学会   代議員  

    2020年10月 - 2022年10月   

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    団体区分:学協会

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  • 公益社団法人日本化学会近畿支部   幹事  

    2020年3月 - 2022年2月   

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    団体区分:学協会

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  • 日本バイオマテリアル学会   評議員  

    2018年4月 - 現在   

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    団体区分:学協会

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  • 公益社団法人高分子学会関西支部   第84回高分子若手研究会[関西] 世話人  

    2015年8月   

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論文

  • UCST-Type Thermoresponsive Sol–Gel Transition Triblock Copolymer Containing Zwitterionic Polymer Blocks 招待 査読

    Akifumi Kawamura, Ryogo Takahashi, Takashi Miyata

    Gels   10 ( 5 )   288 - 288   2024年4月

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    担当区分:筆頭著者, 責任著者   掲載種別:研究論文(学術雑誌)   出版者・発行元:MDPI AG  

    Thermoresponsive sol–gel transition polymers are of significant interest because of their fascinating biomedical applications, including as drug reservoirs for drug delivery systems and scaffolds for tissue engineering. Although extensive research has been conducted on lower critical solution temperature (LCST)-type sol–gel transition polymers, there have been few reports on upper critical solution temperature (UCST)-type sol–gel transition polymers. In this study, we designed an ABA-type triblock copolymer composed of a poly(ethylene glycol) (PEG) block and zwitterionic polymer blocks that exhibit UCST-type thermoresponsive phase transitions. A sulfobetaine (SB) monomer with both ammonium and sulfonate (–SO3) groups in its side chain or a sulfabetaine (SaB) monomer with both ammonium and sulfate (–OSO3) groups in its side chain was polymerized from both ends of the PEG block via reversible addition–fragmentation chain-transfer (RAFT) polymerization to obtain PSB-PEG-PSB and PSaB-PEG-PSaB triblock copolymers, respectively. Although an aqueous solution containing the PSB-PEG-PSB triblock copolymer showed an increase in viscosity upon cooling, it did not undergo a sol-to-gel transition. In contrast, a sol-to-gel transition was observed when a phosphate-buffered saline containing PSaB-PEG-PSaB was cooled from 80 °C to 25 °C. The PSaB blocks with –OSO3 groups exhibited a stronger dipole–dipole interaction than conventional SB with –SO3 groups, leading to intermolecular association and the formation of a gel network composed of PSaB assemblies bridged with PEG. The fascinating UCST-type thermoresponsive sol–gel transition properties of the PSaB-PEG-PSaB triblock copolymer suggest that it can provide a useful platform for designing smart biomaterials, such as drug delivery reservoirs and cell culture scaffolds.

    DOI: 10.3390/gels10050288

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  • Core–shell Microgels Having Zwitterionic Hydrogel Core and Temperature-responsive Shell Prepared via Inverse Miniemulsion RAFT Polymerization 査読

    Mitsuhide Sasaoka, Akifumi Kawamura, Takashi Miyata

    Polymer Chemistry   13 ( 23 )   3489 - 3497   2022年6月

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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)   出版者・発行元:Royal Society of Chemistry ({RSC})  

    The temperature-responsive core–shell microgels comprising PMPC core and side-chain oligo(ethylene glycol) polymer shell were prepared via inverse miniemulsion RAFT polymerization using a water-soluble emulsifier with RAFT agent terminus.

    DOI: 10.1039/d2py00425a

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  • Weakly Acidic pH and Reduction Dual Stimuli-Responsive Gel Particles 査読

    Akifumi Kawamura, Ayaka Harada, Shunsuke Ueno, Takashi Miyata

    Langmuir   37 ( 39 )   11484 - 11492   2021年10月

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:American Chemical Society (ACS)  

    DOI: 10.1021/acs.langmuir.1c01677

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  • Reductively Responsive Gel Capsules Prepared Using a Water-Soluble Zwitterionic Block Copolymer Emulsifier 査読

    Hiroshi Nakaura, Akifumi Kawamura, Takashi Miyata

    Langmuir   35 ( 5 )   1413 - 1420   2019年2月

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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)   出版者・発行元:American Chemical Society ({ACS})  

    DOI: 10.1021/acs.langmuir.8b01608

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  • Design of nano- and micro-structured molecule-responsive hydrogels 査読

    Akifumi Kawamura

    POLYMER JOURNAL   49 ( 11 )   751 - 757   2017年11月

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:NATURE PUBLISHING GROUP  

    Stimuli-responsive hydrogels have attracted considerable attention for use as smart materials, such as in molecular sensors and drug delivery systems. With a focus on their crosslinking density, we have prepared various molecule-responsive hydrogels that undergo volume changes in response to target molecules based on the association/dissociation of molecular complexes that act as crosslinkers. Recent developments in polymerization techniques enabled us to design various types of polymer nanomaterials. This focus review provides a short overview of our recent studies on the nano-and micro-structured molecule-responsive hydrogels prepared using various polymerization techniques, such as photopolymerization, surface-initiated atom transfer radical polymerization and soap-free emulsion polymerization. The nano-and micro-structured molecule-responsive hydrogels showed not only rapid swelling/shrinkage in response to a target molecule owing to their large surface area but also smart functions, such as autonomous molecule-responsive microchannel flow regulation and highly sensitive detection of a target molecule. The smart functions of nano-and micro-structured molecule-responsive hydrogels can provide tools for constructing, for example, sensors, microdevices and smart biomaterials.

    DOI: 10.1038/pj.2017.54

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  • Effect of Gold Nanoparticle Size on Regulated Catalytic Activity of Temperature-Responsive Polymer−Gold Nanoparticle Hybrid Microgels 査読

    Palida Pongsanon, Akifumi Kawamura, Hideya Kawasaki, Takashi Miyata

    Gels   10 ( 6 )   357 - 357   2024年5月

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    掲載種別:研究論文(学術雑誌)   出版者・発行元:MDPI AG  

    Gold nanoparticles (AuNPs) possess attractive electronic, optical, and catalytic properties, enabling many potential applications. Poly(N-isopropyl acrylamide) (PNIPAAm) is a temperature-responsive polymer that changes its hydrophilicity upon a slight temperature change, and combining PNIPAAm with AuNPs allows us to modulate the properties of AuNPs by temperature. In a previous study, we proposed a simpler method for designing PNIPAAm–AuNP hybrid microgels, which used an AuNP monomer with polymerizable groups. The size of AuNPs is the most important factor influencing their catalytic performance, and numerous studies have emphasized the importance of controlling the size of AuNPs by adjusting their stabilizer concentration. This paper focuses on the effect of AuNP size on the catalytic activity of PNIPAAm–AuNP hybrid microgels prepared via the copolymerization of N-isopropyl acrylamide and AuNP monomers with different AuNP sizes. To quantitatively evaluate the catalytic activity of the hybrid microgels, we monitored the reduction of 4-nitrophenol to 4-aminophenol using the hybrid microgels with various AuNP sizes. While the hybrid microgels with an AuNP size of 13.0 nm exhibited the highest reaction rate and the apparent reaction rate constant (kapp) of 24.2 × 10−3 s−1, those of 35.9 nm exhibited a small kapp of 1.3 × 10−3 s−1. Thus, the catalytic activity of the PNIPAAm–AuNP hybrid microgel was strongly influenced by the AuNP size. The hybrid microgels with various AuNP sizes enabled the reversibly temperature-responsive on–off regulation of the reduction reaction.

    DOI: 10.3390/gels10060357

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  • Straightforward preparation of a tough and stretchable ion gel 査読

    Aya Saruwatari, Yuji Kamiyama, Akifumi Kawamura, Takashi Miyata, Ryota Tamate, Takeshi Ueki

    Soft Matter   2024年

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    掲載種別:研究論文(学術雑誌)   出版者・発行元:Royal Society of Chemistry (RSC)  

    A facile preparation method of an ion gel that exhibits high strength and repeated stretchability is realized. A number of polymer chain entanglements in addition to a small number of chemical cross-links support mechanical properties of gel.

    DOI: 10.1039/d4sm00628c

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  • Design of dual stimuli-responsive gels with physical and chemical properties that vary in response to light and temperature and cell behavior on their surfaces 査読

    Masaaki Okihara, Akana Matsuda, Akifumi Kawamura, Takashi Miyata

    Polymer Journal   56 ( 3 )   193 - 204   2023年12月

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    掲載種別:研究論文(学術雑誌)   出版者・発行元:Springer Science and Business Media LLC  

    Abstract

    Cell behaviors are highly sensitive to the surrounding environment. Therefore, in regulating cells, biomaterial substrates should be designed so their properties are similar to the surrounding environments of the cells. For cell regulation, we designed dual stimuli-responsive gels whose physical (elastic modulus) and chemical (hydrophilicity) properties can be changed by varying the UV exposure time and temperature, respectively. A dual stimuli-responsive polymer with photodimerizable groups and temperature-responsive moieties was prepared by copolymerizing 7-methacryloyloxycoumarin (MAC) and methoxyoligoethylene glycol methacrylate (OEGMA). The resulting polymers (P(MAC-co-OEGMA)) had lower critical solution temperatures (LCSTs), which depended on the compositions. A buffer solution containing P(MAC-co-OEGMA) was exposed to ultraviolet light (UV) for gelation, and the elastic modulus increased with increasing exposure time. The cell behavior, including adhesion and spreading, on the surfaces of these gels was investigated. Most of the cells adhered to P(MAC-co-OEGMA) gels with higher elastic moduli, and the cells were spread more effectively at temperatures above the LCST. This was because cell adhesion and spreading were strongly influenced by the physical and chemical properties of the P(MAC-co-OEGMA) gels, which were regulated by varying the UV exposure time and temperature.

    DOI: 10.1038/s41428-023-00865-7

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    その他リンク: https://www.nature.com/articles/s41428-023-00865-7

  • Controllable Catalytic Activity of Temperature-Responsive Polymer Hybrid Microgels Designed Using a Gold Nanoparticle Monomer with Polymerizable Groups 査読

    Palida Pongsanon, Yoshiko Oota, Akifumi Kawamura, Hideya Kawasaki, Takashi Miyata

    Macromolecules   56 ( 23 )   9853 - 9865   2023年11月

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    掲載種別:研究論文(学術雑誌)   出版者・発行元:American Chemical Society (ACS)  

    DOI: 10.1021/acs.macromol.3c01659

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  • Reversible Regulation of Drug Release from Chiral Liquid Crystalline Polymer Micelles without Leakage 査読

    Yasuaki Inoue, Yuki Hirano, Akifumi Kawamura, Takashi Miyata

    Macromolecules   56   8298 - 8307   2023年10月

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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:American Chemical Society (ACS)  

    DOI: 10.1021/acs.macromol.3c01049

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  • Cell patterning on photocrosslinkable polymer films with micropatternable surfaces 査読

    Takafumi Noguchi, Misato Higashino, Neiro Kodama, Akifumi Kawamura, Takashi Miyata

    Responsive Materials   1 ( 1 )   e20230007   2023年7月

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    掲載種別:研究論文(学術雑誌)   出版者・発行元:Wiley  

    Abstract

    The regulation of cell behavior is crucial for understanding many fundamental biological processes and designing novel medical devices. Nano/micropatterning has been developed as a means of controlling cellular properties and behaviors. Using cinnamoyl groups that have undergone photodimerization, we have prepared facile photopatterning films with adjustable surface properties for cell patterning via simple steps. Our strategy for controlling surface properties uses the decrease in free volume induced by photocrosslinking. This paper describes the surface‐patterning properties of photocrosslinkable polymer films and the cell adhesion to their micropatterned surfaces. Upon culturing cells on micropatterned surfaces, preferential cell adhesion, alignment and proliferation are observed in the unexposed regions. Additionally, diverse surface patterns of photocrosslinkable polymer films have been fabricated using various photomasks, enabling effective control of cell adhesion and alignment. The ability to regulate cellular behavior via microfabricated surfaces of photocrosslinkable polymer films enables a new and facile approach for designing scaffolds for the development of novel advanced materials, tissue engineering, and regenerative medicine.

    DOI: 10.1002/rpm.20230007

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  • Relatively homogeneous network structures of temperature-responsive gels synthesized <i>via</i> atom transfer radical polymerization 査読

    Chisa Norioka, Akifumi Kawamura, Takashi Miyata

    Soft Matter   19 ( 14 )   2505 - 2513   2023年

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    掲載種別:研究論文(学術雑誌)   出版者・発行元:Royal Society of Chemistry (RSC)  

    DLS measurements revealed that temperature-responsive gels prepared by ATRP have more homogeneous networks than those by free radical polymerization. The standard deviation of the scattered intensity is used to quantify the network inhomogeneity.

    DOI: 10.1039/d3sm00044c

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  • Design of molecularly imprinted hydrogels with thermoresponsive drug binding sites 査読

    Yuto Toyoshima, Akifumi Kawamura, Yoshinori Takashima, Takashi Miyata

    Journal of Materials Chemistry B   10   6644 - 6654   2022年4月

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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  

    Drug delivery systems (DDS) regulate the spatiotemporal distribution of drugs in vivo to maximize efficacy and minimize side effects. Stimuli-responsive hydrogels, which exhibit a drastic change in volume in response to external stimuli such as temperature and pH, have attracted considerable interest as drug reservoirs for self-regulating DDS, as stimuli-responsive changes in the network size can regulate drug diffusion. However, such hydrogels have the disadvantage of leaking drugs even in the absence of stimulation. Proteins such as hemoglobin have dynamic molecular binding sites that modify their binding capacities by their conformational changes induced when an effector molecule binds to allosteric sites. Such dynamic binding sites are useful for loading drugs into reservoirs because their conformational changes can be used to control drug loading and release. In this study, we prepared thermoresponsive hydrogels with a controlled drug binding capacity to design drug reservoirs capable of both suppressing drug leakage below the transition temperature and accelerating drug release above it. Dynamic molecular binding sites were created by molecular imprinting that used 4,4 '-diaminodiphenyl sulfone (dapsone) as the model drug, beta-cyclodextrin (CD) as the ligand, and N-isopropylacrylamide as the primary monomer. The molecularly imprinted (MIP) and nonimprinted (NIP) hydrogels with CD ligands, as well as the poly(N-isopropylacrylamide) (PNIPAAm) hydrogels without CD ligands, drastically shrunk above their transition temperature because of the PNIPAAm major chains changing conformation from a hydrophilic random coil to a hydrophobic globule as temperature increased. Because the MIP hydrogel has dynamic molecular binding sites, it absorbs a larger amount of dapsone than the NIP hydrogels in an aqueous solution below the transition temperature. The amount of dapsone adsorbed into the MIP hydrogel significantly decreased with increasing temperatures above 37 degrees C, despite the fact that the hydrophobic interaction between the polymer chains and dapsone became strong. The decrease in dapsone adsorption capability of the MIP hydrogel is due to a conformational change from a swollen to a shrunken state as temperature increases. The MIP hydrogel suppressed drug leakage below its transition temperature due to the high binding capacity of dynamic binding sites, but accelerated the drug release above its transition temperature due to the collapse of dynamic molecular binding sites, in contrast to the drug release behavior of general PNIPAAm-based hydrogels. Thus, the thermoresponsive MIP hydrogels with dynamic molecular binding sites regulated drug release in response to a change in temperature.

    DOI: 10.1039/d2tb00325b

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  • Photoresponsive Gelation of Four-Armed Poly(ethylene glycol) with Photodimerizable Groups 査読

    Masaaki Okihara, Kohei Okuma, Akifumi Kawamura, Takashi Miyata

    Gels   8 ( 3 )   183 - 183   2022年3月

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    掲載種別:研究論文(学術雑誌)   出版者・発行元:{MDPI} {AG}  

    Standard hydrogels prepared by free radical polymerization (FRP) have heterogeneous structures with a wide mesh size distribution, which affect their mechanical and separation properties. Recent research has identified four-armed poly(ethylene glycol) (tetra-PEG) as a solution to this problem. tetra-PEG gels with a homogeneous network can be prepared and applied as high-strength gels and cell-culture substrates by reacting two types of tetra-PEG with different reactive groups at the ends. In this study, we report a photoresponsive tetra-PEG that undergoes a phase transition from a sol to a gel state in response to light. tetra-PEGs containing cinnamoyl and maleimide groups at the ends of the four-armed chains were found to gel when exposed to light. The effects of polymer concentration and light irradiation time on the gelation of tetra-PEG containing photodimerization groups were investigated. The results showed that the elastic modulus of the gel increased with the increase in the light irradiation time.

    DOI: 10.3390/gels8030183

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  • Photoresponsive behaviour of zwitterionic polymer particles with photodimerizable groups on their surfaces. 査読 国際誌

    Takashi Miyata, Takayuki Namera, Yihua Liu, Akifumi Kawamura, Tetsuji Yamaoka

    Journal of materials chemistry. B   10 ( 14 )   2637 - 2648   2022年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    Polymer particles with precise diameters have been used as building blocks for fabricating well-defined and nanostructured materials. Polymer particles as building blocks for medical applications require both easily spatiotemporal manipulation and good biocompatibility. In this study, we designed zwitterionic polymer particles with photodimerizable groups on their surfaces and used ultraviolet (UV) light irradiation to photo-assemble them in aqueous media. After synthesizing zwitterionic polymer particles with diameters ranging from 100-200 nm via soap-free emulsion polymerization, maleimide moieties as photodimerizable groups were introduced onto the particle surfaces. UV light irradiation to an aqueous dispersion of zwitterionic polymer particles with photodimerizable groups induced their photo-assembling because interparticle bonding forms by photodimerization of the photodimerizable groups on the particle surfaces. The zwitterionic surface of their particle-assembled films effectively suppressed protein adsorption, cell adhesion, and platelet adhesion. The photoresponsive behaviour and bioinert surface of the zwitterionic polymer particles with photodimerizable groups indicate that they have several potential applications as bioinert building blocks for designing well-defined and nanostructured biomaterials used in biosensors, bioseparation and cell culture, and for modifying and repairing biomaterial surfaces in situ.

    DOI: 10.1039/d1tb02342j

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  • Photoresponsive Polymer Films with Directly Micropatternable Surfaces Based on the Change in Free Volume by Photo-Crosslinking 査読

    Takafumi Noguchi, Nobuhiro Akioka, Yuri Kojima, Akifumi Kawamura, Takashi Miyata

    Advanced Materials Interfaces   9 ( 9 )   2101965   2022年1月

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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  

    Photoresponsive polymers, whose structures or properties change when exposed to ultraviolet (UV) light, have been studied for the fabrication of micro- and nano-devices for various applications. Herein, photoresponsive polymer films are investigated with directly micropatternable surfaces formed by only UV exposure without the development process using solvents. The photoresponsive polymer films are designed based on the decrease in free volume induced by the photodimerization of cinnamoyl groups. The photoresponsive polymers are synthesized by copolymerizing a monomer with photodimerizable groups and a poly(dimethylsiloxane) macromonomer. Micropatterns are easily formed on the film surfaces by only UV exposure using photomasks. The micropatterns are achieved due to the decrease in the film thickness with a decrease in the free volume induced by photo-crosslinking. Using a decrease in free volume by photo-crosslinking leads to wide practical applications with simple processes and low costs.

    DOI: 10.1002/admi.202101965

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  • Amphiphilic Liquid Crystalline Polymer Micelles That Exhibit a Phase Transition at Body Temperature 査読

    Yasuaki Inoue, Kazuhito Takada, Akifumi Kawamura, Takashi Miyata

    ACS Applied Materials Interfaces   14(28), 31513-31524 ( 28 )   31513 - 31524   2022年

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    掲載種別:研究論文(学術雑誌)  

    DOI: 10.1021/acsami.2c00592

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  • A universal method to easily design tough and stretchable hydrogels 査読

    Chisa Norioka, Yuino Inamoto, Chika Hajime, Akifumi Kawamura, Takashi Miyata

    NPG Asia Materials   13 ( 1 )   34   2021年4月

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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 Science and Business Media LLC  

    <title>Abstract</title>Hydrogels are flexible materials that have high potential for use in various applications due to their unique properties. However, their applications are greatly restricted by the low mechanical performance caused by high water content and inhomogeneous networks. This paper reports a universal strategy for easily preparing hydrogels that are tough and stretchable without any special structures or complicated processes. Our strategy involves tuning the polymerization conditions to form networks with many polymer chain entanglements to achieve energy dissipation. Tough and stretchable hydrogels can be prepared by free radical polymerization with a high monomer concentration and low cross-linker content to optimize the balance between physical and chemical cross-links by entanglements and covalent bonds, respectively. The strategy of using polymer chain entanglements for energy dissipation allows us to overcome the limitation of low mechanical performance, which leads to the wide practical use of hydrogels.

    DOI: 10.1038/s41427-021-00302-2

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    その他リンク: http://www.nature.com/articles/s41427-021-00302-2

  • Thermoresponsive liquid crystalline polymer membranes that undergo phase transition at body temperature 査読

    Akifumi Kawamura

    Journal of Membrane Science   588   117213   2019年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.memsci.2019.117213

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  • Preparation of molecularly imprinted hydrogel layer SPR sensor chips with lectin-recognition sites via SI-ATRP 査読

    Rinyarat Naraprawatphong, Akifumi Kawamura, Takashi Miyata

    Polymer Journal   50 ( 3 )   261 - 269   2018年3月

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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:Nature Publishing Group  

    Molecularly imprinted hydrogel layers with lectin-recognition sites were prepared on surface plasmon resonance (SPR) sensor chips via surface-initiated atom transfer radical polymerization (SI-ATRP) combined with molecular imprinting. The lectin-imprinted hydrogel layer sensor chips showed larger SPR signal change in response to a target lectin than nonimprinted hydrogel layer sensor chips. The larger SPR signal change was attributed to the strong affinity constant of the lectin-imprinted hydrogel layer for the target lectin. These results suggest that molecular recognition sites for the lectin were formed within the hydrogel layers by molecular imprinting. On the other hand, the SPR signal change of the lectin-imprinted hydrogel layer chip in the presence of other lectin was very small. Poly(2-methacryloxyethyl phosphorylcholine) as a main chain of the hydrogel layer inhibited nonspecific adsorption of other lectin. This paper describes that SI-ATRP with biomolecular imprinting is a useful method to design highly sensitive and selective SPR sensor chips with molecular recognition sites for a target lectin.

    DOI: 10.1038/s41428-017-0013-7

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  • Design of Protein-responsive Micro-sized Hydrogels for Self-regulating MIcrofluidic Systems 査読

    Mayu Hirayama, Kazuhiro Tsuruta, Akifumi Kawamura, Masayuki Ohara, Kan Shoji, Ryuji Kawano, Takashi Miyata

    Journal of Micromechanics and Microengineering   28 ( 3 )   034002   2018年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

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  • Biomolecularly stimuli-responsive tetra-poly (ethylene glycol) that undergoes sol-gel transition in response to a target biomolecule 査読

    Chisa Norioka, Kazuma Okita, Miho Mukada, Akifumi Kawamura, Takashi Miyata

    Polymer Chemistry   8 ( 41 )   6378 - 6385   2017年11月

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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  

    Stimuli-responsive polymers that undergo a sol-gel transition in response to changes in environmental factors such as pH and temperature have attracted considerable attention for biomedical applications such as drug reservoirs for controlled release and scaffolds for tissue engineering. Although numerous stimuli-responsive polymers that undergo a sol-gel transition have been reported, the literature contains few accounts of biomolecularly stimuli-responsive polymers that undergo a sol-gel transition in response to a specific biomolecule. In previous studies, we designed biomolecule-responsive hydrogels that undergo changes in volume in response to a target biomolecule; the strategy involves using biomolecular complexes as dynamic cross-links in the gel networks. In the present study, we designed biotin-conjugated four-armed poly(ethylene glycol) (biotinylated Tetra-PEG) as biomolecular stimuli-responsive sol-gel transition polymers that underwent the phase transition from a sol to a gel state in response to avidin as a target biomolecule. When avidin that forms a biomolecular complex with biotin was added to a buffer solution containing biotinylated Tetra-PEG, the solution transformed to a gel state immediately. However, the addition of a buffer solution with free biotin to the resulting hydrogel induced its dissociation to a sol state. The sol-gel transition of a buffer solution with biotinylated Tetra-PEG was directly affected by polymer concentration and the biotin/avidin molar ratio. The phase diagram of the sol-gel transition of biotinylated Tetra-PEG in a buffer solution as a function of polymer concentration and the biotin/avidin molar ratio is presented.

    DOI: 10.1039/c7py01370a

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  • Mechanical and responsive properties of temperature-responsive gels prepared via atom transfer radical polymerization 査読

    Chisa Norioka, Akifumi Kawamura, Takashi Miyata

    POLYMER CHEMISTRY   8 ( 39 )   6050 - 6057   2017年10月

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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  

    Temperature-responsive poly(N-isopropylacrylamide) (PNIPAAm) gels were prepared via atom transfer radical polymerization (ATRP), and their mechanical and responsive properties were investigated from the viewpoint of their network homogeneity. When the PNIPAAm gels were prepared by ATRP and free radical polymerization (FRP) at a low temperature, no difference was observed in the mechanical properties. However, the PNIPAAm gels prepared via ATRP at room temperature showed a higher elastic modulus and greater temperature-responsive change than the gels prepared via FRP. The temperature-responsive shrinkage rate of the PNIPAAm gel prepared via ATRP was slower than that of the gel prepared via FRP. Dynamic light scattering (DLS) measurements revealed that these results can be attributed to the more homogeneous network structure in the PNIPAAm gel prepared via ATRP than in the gel prepared via FRP.

    DOI: 10.1039/c7py01323j

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  • Conformationally Regulated Molecular Binding and Release of Molecularly Imprinted Polypeptide Hydrogels That Undergo Helix-Coil Transition 査読

    Kazuya Matsumoto, Akifumi Kawamura, Takashi Miyata

    MACROMOLECULES   50 ( 5 )   2136 - 2144   2017年3月

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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  

    Polypeptides have inherent secondary structures, such as alpha-helix,) beta-sheet, and random coil structures, depending on their amino acid sequence. beta-Cyclodextrins (CDs) as ligands of molecular recognition sites were introduced into poly(Llysine) (PLL), which undergoes a structural transition in response to a pH change. CD-introduced PLL (CD-PLL) hydrogels with dynamic molecular recognition sites for bisphenol A (BPA) were strategically designed by molecular imprinting, where BPA was used as a template molecule with a minute amount of cross-linkers. The resulting BPA-imprinted CD-PLL hydrogels with a random coil structure underwent a change in volume in response to the target BPA because the ligand CDs formed a complex with BPA. Additionally, a change in pH induced a structural transition of the CD-PLL chains from the random coil to an a-helix, followed by a conformational change of the molecular recognition sites within the BPA-imprinted CD-PLL hydrogels. As a result, BPA adsorption into the BPA-imprinted CD-PLL hydrogels strongly depended on pH. The molecular recognition ability of the BPA-imprinted CD-PLL hydrogels was controlled by the helix coil transition of the PLL chains. BPA, as a model drug, was loaded within the CD-PLL hydrogel networks by molecular imprinting, and the BPA template was not extracted from the hydrogel networks. The drug release from the drug-loaded CD-PLL hydrogel was regulated by the pH-responsive structural transition of the PLL chains, which could control the stability of the inclusion complex between the drugs and CD ligands. The fascinating properties of the BPA-imprinted CD-PLL hydrogels with dynamic molecular recognition sites suggest that they exhibit potential as suitable drug carriers inspired from the allosteric effects of proteins.

    DOI: 10.1021/acs.macromol.6b02688

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  • QCM sensing of bisphenol A using molecularly imprinted hydrogel/conducting polymer matrix

    Kazuya Matsumoto, Brylee David B. Tiu, Akifumi Kawamura, Rigoberto C. Advincula, Takashi Miyata

    POLYMER JOURNAL   48 ( 4 )   525 - 532   2016年4月

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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:NATURE PUBLISHING GROUP  

    Molecular imprinting is a well-known fabrication technique for designing artificial receptors and molecular sensors. The technique resembles a lock and key mechanism and utilizes shape-complementary cavities within polymeric materials as molecular recognition sites for various relevant molecules. In this study, we prepared molecularly imprinted polypeptide gel layers based on cyclodextrin-modified poly(L-lysine) (CD-PLL) on quartz crystal microbalance (QCM) sensor chips and investigated their molecular recognition behaviors for bisphenol A (BPA) using the QCM technique. With BPA as the template and CD as its ligand, the BPA-imprinted CD-PLL gel layers were prepared on electropolymerized polyterthiophene films, which were formed using electrochemical QCM (EQCM). The BPA-imprinted CD-PLL gel layer chip exhibited a much greater QCM response than the non-imprinted gel layer chip in an aqueous BPA solution. The greater response of the BPA-imprinted CD-PLL gel layer chip means that molecular imprinting enabled CD ligands to be arranged at optimal positions for forming molecular recognition sites. The combination of in situ electropolymerization using EQCM and molecular imprinting provides useful methods for fabricating highly selective and sensitive sensor devices for monitoring minute amounts of BPA in water.

    DOI: 10.1038/pj.2016.23

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  • Development of protein-recognition SPR devices by combination of SI-ATRP with biomolecular imprinting using protein ligands 査読

    Rinyarat Naraprawatphong, Genta Kawanaka, Masayoshi Hayashi, Akifumi Kawamura, Takashi Miyata

    Molecular Imprinting   4 ( 1 )   21 - 30   2016年1月

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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:Walter de Gruyter {GmbH}  

    DOI: 10.1515/molim-2016-0003

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  • Structural Transition of pH-responsive Poly(L-lysine) Hydrogel Prepared via Chemical Crosslinking

    Kazuya Matsumoto, Akifumi Kawamura, Takashi Miyata

    CHEMISTRY LETTERS   44 ( 10 )   1284 - 1286   2015年10月

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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:CHEMICAL SOC JAPAN  

    Poly(L-lysine) (PLL) undergoes structural change from alpha-helix to random coil in response to a change in pH in an aqueous solution. By chemical crosslinking of PLL with ethylene glycol diglycidyl ether (EGDE), we prepared pH-responsive hydrogels that undergo a change in volume and conformation between a-helix and random coil in response to a change in pH. The difference in transition pH between a PLL linear polymer and a PLL hydrogel revealed that chemical crosslinking stabilized the helical structure of PLL chains in hydrogel networks.

    DOI: 10.1246/cl.150464

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  • Preparation of Molecule-Responsive Microsized Hydrogels via Photopolymerization for Smart Microchannel Microvalves

    Yusuke Shiraki, Kazuhiro Tsuruta, Junpei Morimoto, Chihiro Ohba, Akifumi Kawamura, Ryo Yoshida, Ryuji Kawano, Tadashi Uragami, Takashi Miyata

    MACROMOLECULAR RAPID COMMUNICATIONS   36 ( 6 )   515 - 519   2015年3月

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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  

    Microdevices designed for practical environmental pollution monitoring need to detect specific pollutants such as dioxins. Bisphenol A (BPA) has been widely used as a monomer for the synthesis of polycarbonate and epoxy resins. However, the recent discovery of its high potential ability to disrupt human endocrine systems has made the development of smart systems and microdevices for its detection and removal necessary. Molecule-responsive microsized hydrogels with -cycrodextrin (-CD) as ligands are prepared by photopolymerization using a fluorescence microscope. The molecule-responsive micro-hydrogels show ultra-quick shrinkage in response to target BPA. Furthermore, the flow rate of a microchannel is autonomously regulated by the molecule-responsive shrinking of their hydrogels as smart microvalves.

    DOI: 10.1002/marc.201400676

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  • Design of molecule-responsive organic–inorganic hybrid nanoparticles bearing cyclodextrin as ligands

    Akifumi Kawamura, Tomoya Katoh, Tadashi Uragami, Takashi Miyata

    Polymer Journal   47 ( 2 )   206 - 211   2015年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1038/pj.2014.122

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  • Formation of Thin Molecularly Imprinted Hydrogel Layers with Lectin Recognition Sites on SPR Sensor Chips by Atom Transfer Radical Polymerization

    Yoshiaki Kuriu, Akifumi Kawamura, Tadashi Uragami, Takashi Miyata

    CHEMISTRY LETTERS   43 ( 6 )   825 - 827   2014年6月

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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:CHEMICAL SOC JAPAN  

    We prepared lectin-imprinted hydrogel layers on surface plasmon resonance (SPR) sensor chips by atom transfer radical polymerization (ATRP). In a buffer solution with a target protein, the SPR signal and binding constant of the lectin-imprinted hydrogel layer chip were much larger than those of the nonimprinted hydrogel layer chip prepared without using a template lectin. By molecular imprinting with ATRP, recognition sites for the target lectin were formed within thin hydrogel layers on the SPR sensor chips. The lectin-imprinted hydrogel layer chips with recognition sites for target protein are candidates for highly sensitive sensor devices for an SPR sensing system.

    DOI: 10.1246/cl.140103

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  • Target molecule-responsive hydrogels designed via molecular imprinting using bisphenol A as a template

    Akifumi Kawamura, Tadahiro Kiguchi, Takeshi Nishihata, Tadashi Uragami, Takashi Miyata

    CHEMICAL COMMUNICATIONS   50 ( 76 )   11101 - 11103   2014年

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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  

    Target molecule-responsive hydrogels with beta-cyclodextrin (beta-CD) were prepared via molecular imprinting using bisphenol A (BPA) as a template. BPA-imprinted hydrogels showed greater shrinkage than non-imprinted hydrogels because CD ligands arranged at suitable positions formed CD-BPA-CD complexes that acted as crosslinks.

    DOI: 10.1039/c4cc01187b

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  • SPR Signals of Three-dimensional Antibody-immobilized Gel Layers Formed on Sensor Chips by Atom Transfer Radical Polymerization

    Yoshiaki Kuriu, Michiko Ishikawa, Akifumi Kawamura, Tadashi Uragami, Takashi Miyata

    CHEMISTRY LETTERS   41 ( 12 )   1660 - 1662   2012年12月

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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:CHEMICAL SOC JAPAN  

    We prepared antibody-immobilized gel layers on surface plasmon resonance (SPR) sensor chips by atom transfer radical polymerization (ATRP). In a buffer solution with a target antigen, the SPR signal of the antibody-immobilized gel layer chip with an optimal thickness was much larger than that of a directly antibody-immobilized chip prepared by the standard amine coupling method. The antibody-immobilized gel layer chips are candidates as highly sensitive bioconjugated devices for SPR sensing systems. This paper focuses on the relationship between the thickness of the gel layer and the SPR signal in the detection of a target antigen.

    DOI: 10.1246/cl.2012.1660

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  • Synthesis of glucose-responsive bioconjugated gel particles using surfactant-free emulsion polymerization

    Akifumi Kawamura, Yuta Hata, Takashi Miyata, Tadashi Uragami

    COLLOIDS AND SURFACES B-BIOINTERFACES   99   74 - 81   2012年11月

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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  

    Bioconjugated gel particles that have complexes composed of lectin concanavalin A (ConA) and 2-glucosyloxyethyl methacrylate (GEMA) were synthesized by the surfactant-free emulsion copolymerization of N,N-diethylaminoethyl methacrylate (DEAEMA), poly(ethylene glycol) dimethacrylate (PEGDMA). GEMA, and modified-ConA with polymerizable groups. The resultant gel particles having GEMA-ConA complexes (GEMA-ConA gel particles) were colloidally stable in a phosphate buffer solution and had a diameter of approximately 750 nm. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) measurements implied that GEMA-ConA gel particles have core-shell structures consisting of a hydrophobic core of DEAEMA and a hydrophilic shell of GEMA and PEGDMA containing ConA. GEMA-ConA gel particles underwent a change in size in response to glucose in a phosphate buffer solution. The swelling ratio of GEMA-ConA gel particles gradually increased with an increase in the glucose concentration. On the other hand, the swelling ratio of GEMA-ConA gel particles remained unchanged in a phosphate buffer solution containing galactose. The glucose-responsive swelling of GEMA-ConA gel particles was induced by the dissociation of GEMA-ConA complexes acting as reversible cross-links, because free glucose behaved as an inhibitor of GEMA-ConA complexes. These results indicate that GEMA-ConA gel particles can recognize glucose selectively and undergo changes in size in response to the glucose concentration. The smart functions of glucose-responsive gel particles can provide tools for constructing self-regulated drug delivery systems and sensor systems useful for treating diabetes. (C) 2011 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.colsurfb.2011.10.008

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  • Synthesis of novel nucleobase-terminated organosilane and its self-assembly on a substrate

    Takashi Miyata, Akifumi Kawamura, Terumi Meotoiwa, Moritoshi Matsumoto, Tadashi Uragami

    POLYMER JOURNAL   44 ( 6 )   625 - 631   2012年6月

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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:NATURE PUBLISHING GROUP  

    A novel nucleobase-terminated organosilane with nucleobase and ethoxysilane moieties was synthesized by a simple method in which bromouracil reacts with amino-terminated organosilane without solvents. The uracil-terminated organosilane was self-assembled on a hydroxylated surface, and then the uracil-concentrated surface was obtained. The resulting uracil-terminated self-assembled layers were characterized by X-ray photoelectron spectroscopy and ellipsometry. Adenine complementary to uracil was effectively adsorbed onto the resultant uracil-concentrated surface by multiple hydrogen bonds. Herein, a simple method is provided for synthesizing a nucleobase-terminated organosilane and modifying a hydroxylated surface to a nucleobase-concentrated surface. Our method, which uses the self-assembly of nucleobase-terminated organosilanes, facilitates the construction of bioconjugated devices for separating and sensing nucleobases and nucleic acids. Polymer Journal (2012) 44, 625-631; doi:10.1038/pj.2012.41; published online 28 March 2012

    DOI: 10.1038/pj.2012.41

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  • Effect of Enzyme Modification by Well-Defined Multi-Armed Poly(Ethylene Glycol) Synthesized Using Polyamidoamine Dendron

    Atsushi Harada, Takeshi Kato, Akifumi Kawamura, Chie Kojima, Kenji Kono

    JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION   22 ( 12 )   1551 - 1561   2011年

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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:VSP BV  

    Egg white lysozyme was chemically modified by PEGylated PAMAM 1st, 2nd and 3rd generation dendrons, which had 2, 4 and 8 PEG arms, respectively. The number of PEG chains introduced to the lysozyme molecule drastically increased with an increase in dendron generation, although the number of PEGylated PAMAM dendrons introduced decreased due to steric repulsion. The lytic activity of lysozyme to Micrococcus luteus cells was effectively inhibited by conjugating PEGylated PAMAM dendron to the lysozyme, indicating steric stabilization of PEG chains at the surface of lysozyme molecule. In addition, the enzymatic reaction of the lysozyme with oligosaccharide substrate was apparently accelerated by a substrate condensation effect due to the multi-armed structure of PEG. (C) Koninklijke Brill NV, Leiden, 2011

    DOI: 10.1163/092050610X514557

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  • Polyion complex micelles formed from glucose oxidase and comb-type polyelectrolyte with poly(ethylene glycol) grafts

    Akifumi Kawamura, Chie Kojima, Michihiro Iijima, Atsushi Harada, Kenji Kono

    JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY   46 ( 11 )   3842 - 3852   2008年6月

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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  

    The comb-type polyelectrolyte, poly(ethylene glycol)-graft-poly(allyl amine) (PEG-g-PAA), was synthesized to prepare polyion complex (PIC) micelles with Aspergillus Niger Glucose oxidase (GOD). Even after mixing GOD and PEG-g-PAAs with various PEG contents, the resulting mixtures remained transparent but the mixture of GOD and PAA homopolymer immediately precipitated. In the mixtures prepared with a stoichiometric mixing ratio, the formation of PIC micelles with a core-shell structure was suggested from dynamic and static light scattering measurements. Glucose, the substrate for GOD, could easily diffuse into the PIC micelles, and the GOD molecules were active even in the core of the PIC micelles. GOD didn&apos;t lose its enzymatic activity through entrapment into the PIC micelles. (C) 2008 Wiley Periodicals, Inc.

    DOI: 10.1002/pola.22739

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  • Preparation of temperature-responsive polymer gels physically immobilizing core-shell type bioconjugates

    Atsushi Harada, Kunio Johnin, Akifumi Kawamura, Kenji Kono

    JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY   45 ( 24 )   5942 - 5948   2007年12月

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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  

    Poly(N-isopropylacrylamide) (PNIPAAm) gels are temperature-responsive polymer gels; and were prepared by redox polymerization of N-isopropylacrylamide in the presence of N,N&apos;-methylenebisacrylamide as a crosslinking reagent and core-shell type bioconjugates, which were core-crosslinked polyion complex micelles formed from the mixture of bovine pancreas trypsin and poly(ethylene glycol)-block-poly(alpha,beta-aspartic acid). The phase transition temperature of PNIPAAm gels was no change with physically immobilization of bioconjugates. Also, the enzymatic activity of bioconjugates was essentially maintained even in PNIPAAm gels, although enzymatic reaction rate was apparently controlled by temperature, i.e., by the degree of swelling of PNIPAAm gels. Further, the control of enzymatic reaction synchronizing the phase transition of PNIPAAm gels immobilized bioconjugates. PNIPAAm gels could immobilize core-shell type bioconjugates, and were successfully prepared without interfering with the properties of temperature-responsive polymer gels and the bionanoreactor. (c) 2007 Wiley Periodicals, Inc.

    DOI: 10.1002/pola.22347

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  • Self-assembled nano-bioreactor from block ionomers with elevated and stabilized enzymatic function

    Akifumi Kawamura, Atsushi Harada, Kenji Kono, Kazunori Kataoka

    BIOCONJUGATE CHEMISTRY   18 ( 5 )   1555 - 1559   2007年9月

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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  

    Core-cross-linked polyion complex (PIC) micelles entrapping trypsin in the core were prepared by mixing trypsin and poly(ethylene glycol)-block-poly(alpha,beta-aspartic acid) in aqueous medium, followed by the introduction of glutaraldehyde cross-linkages. Trypsin incorporated into the core-cross-linked micelles showed high storage stabilities, and the initial enzymatic activity of trypsin was maintained even after standing for one week at ambient temperature. Further, stable compartmentalization of trypsin into the core-cross-linked micelles led to a unique modulation in the enzymatic functions including an improved thermal tolerability with an increased maximum reaction rate compared to native trypsin.

    DOI: 10.1021/bc070029t

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  • Effect of polycarboxylate blocks on the amidase activity of trypsin through complexation with PEG/polycarboxylate block ionomers

    Atsushi Harada, Yuriko Yoshioka, Akifumi Kawamura, Chie Kojima, Kenji Kono

    MACROMOLECULAR BIOSCIENCE   7 ( 3 )   339 - 343   2007年3月

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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  

    The amidase reaction of trypsin, which is a member of the serine proteinase family, is accelerated by its complexation with block ionomers containing a polycarboxylate block, such as PEG-PAA, PEG-PGA, or PEG-PMA. PEG-PAA and PEG-PGA had similar effects, causing an increase in the k(cat) value and a shift in the pH profile to a lower pH region. On the other hand, PEG-PAAA showed not only an increase in the kcat value, but also a decrease in the activation energy; however, there was no shift in the pH dependence of the initial reaction rate. Such differences might be induced by the difference in pK(a) values of the polycarboxylate block in block ionomers.

    DOI: 10.1002/mabi.200600199

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  • Acceleration of enzymatic reaction of trypsin through the formation of water-soluble complexes with poly(ethylene glycol)-block-poly(alpha,beta-aspartic acid)

    A Kawamura, Y Yoshioka, A Harada, K Kono

    BIOMACROMOLECULES   6 ( 2 )   627 - 631   2005年3月

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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  

    The amidase activity of bovine pancreas trypsin in water-soluble complexes with poly(ethylene glycol)block-poly(alpha,beta-aspartic acid) (PEG-PAA) was evaluated by a colorimetric assay using L-lysine p-nitroanilide as a substrate. The enzymatic reaction of trypsin was accelerated through the complexation with PEG-PAA. By determining the kinetic parameters of the enzymatic reaction of trypsin, it was confirmed that the catalytic rate constant of the complexed trypsin was 15 times higher than that of the native trypsin. From the evaluation of pH dependence of initial reaction rate, it was indicated that this acceleration was induced by a stabilization of the imidazolium ion of the His residue in the catalytic site, the Asp-His-Ser triad, of trypsin due to the Asp units of PEG-PAA. The hydrogen bonded Asp-His pairs are critical constituents in several key enzymatic reactions including serine protease and apurinic endonucleases, and it was expected that the acceleration of the catalytic reaction might occur for other enzymes by the formation of water-soluble complexes with PEG-PAA.

    DOI: 10.1021/bm049198w

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▼全件表示

書籍等出版物

  • Biosensors

    Akifumi Kawamura, Takashi Miyata

    Biomaterials Nanoarchitectonics, Elsevier  2016年2月 

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  • タンパク質をキャッチアンドリリース -標的タンパク質を分離するマイクロ流体システム-

    河村 暁文( 担当: 単著)

    化学  2016年1月 

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  • pH-Responsive Polymers

    Akifumi Kawamura, Takashi Miyata

    Encyclopedia of Polymeric Nanomaterials, Springer-Verlag  2015年6月 

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  • 細胞内デリバリーを指向した二重刺激応答性ゲル微粒子の設計

    河村 暁文( 担当: 単著)

    バイオマテリアル-生体材料-  2015年1月 

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  • Biologically Stimuli-Responsive Hydrogels

    Akifumi Kawamura, Takashi Miyata

    Intelligent Stimuli-Responsive Materials: From Well-Defined Nanostructures to Applications (ed. Q. Li)  2013年10月 

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  • 生体分子応答性ゲルの創製

    河村 暁文, 宮田 隆志

    機能材料  2012年 

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  • 高分子修飾による酵素の機能化

    河村 暁文( 担当: 単著)

    理工学と技術  2012年 

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▼全件表示

MISC

  • 双性イオンポリマーの界面特性を利用したソフトマテリアルの創出と未来展望 招待

    河村 暁文

    日本接着学会誌   60 ( 11 )   308 - 310   2024年11月

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    担当区分:筆頭著者, 責任著者   記述言語:日本語  

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  • 界面化学的手法を用いた機能性ソフトナノマテリアルの設計 招待 査読

    河村 暁文

    日本接着学会誌   59 ( 3 )   1 - 9   2024年3月

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    担当区分:筆頭著者, 責任著者   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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  • 生体分子応答性ゲルの創製 (特集 スマートゲルの最新動向)

    河村 暁文, 宮田 隆志

    機能材料   32 ( 3 )   50 - 56   2012年3月

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    記述言語:日本語   出版者・発行元:シーエムシー出版  

    CiNii Books

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講演・口頭発表等

  • Reducing-Environment-Responsive Gel Capsules Prepared Via Inverse Miniemulsion Periphery RAFT Polymerization from Water-Soluble Emulsifier Stabilizing W/O Emulsions

    Akifumi Kawamura, Hiroshi Nakaura, Takashi Miyata

    First International Conference on 4D Materials and Systems (4DMS)  2018年8月 

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    開催年月日: 2018年8月

    開催地:山形大学米沢キャンパス,山形  

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  • 界面化学を利用した機能性ソフトナノマテリアルの創製

    河村 暁文

    第1回先端機能分子材料シンポジウム  2018年3月 

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    開催年月日: 2018年3月

    開催地:東京工業大学,東京  

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  • 外部刺激により形状が変化するスマートポリマーの設計と細胞制御への展開

    河村 暁文, 宮田 隆志

    日本材料学会第48回生体・医療材料部門委員会  2017年12月 

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    開催年月日: 2017年12月

    開催地:大阪大学吹田キャンパス,大阪  

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  • エマルションを利用した細胞内環境応答性なのトランスポーターの設計

    河村 暁文

    27th Annual Meeting of MRS-Japan 2017  2017年12月 

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    開催年月日: 2017年12月

    開催地:横浜市開港記念会館,神奈川  

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  • 生体内環境認識能を有する刺激応答性ゲル微粒子の設計とそのバイオ応用

    河村 暁文

    第65回高分子学会年次大会  2016年5月 

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    開催年月日: 2016年5月

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  • Design of Biologically Stimuli-responsive Gel Particles for Biomedical Applications

    Akifumi Kawamura, Shunsuke Ueno, Takashi Miyata

    The 2015 International Symposium for Advanced Materials Research (ISAMR2015)  2015年8月 

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    開催年月日: 2015年8月

    開催地:Sun Moon Lake, Taiwan  

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  • Design of Dual Stimuli-responsive Gel Particles as an Intracellular Delivery Vehicle

    Akifumi Kawamura, Shunsuke Ueno, Tadashi Uragami, Takashi Miyata

    第36回日本バイオマテリアル学会大会  2014年11月 

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    開催年月日: 2014年11月

    開催地:タワーホール船堀,東京  

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  • Design of Dual Stimuli-responsive Gel Particles as an Intracellular Delivery Vehicle

    Akifumi Kawamura

    22nd Annual Meeting of Korean Society for Biomaterials  2014年11月 

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    開催年月日: 2014年11月

    開催地:The Korea Science and Technology Center, Seoul, Korea  

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  • エマルション技術を利用した機能性高分子微粒子の合成

    河村 暁文

    2021年11月 

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    開催地:Web開催  

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  • 高分子の自己組織化を利用したスマートソフトマテリアルの創製

    河村 暁文

    2020年8月 

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    開催地:Web開催  

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産業財産権

  • ポリマー

    河村暁文, 宮田隆志, 糸満璃香

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    出願人:学校法人 関西大学

    出願番号:特願2022-062375  出願日:2022年4月

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  • 高強度ゲル体およびその作製方法ならびにハイドロゲルおよびその作製方法

    宮田 隆志, 河村 暁文, 乗岡 智沙

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    出願人:学校法人 関西大学

    出願番号:特願2019-085035  出願日:2019年4月

    公開番号:特開2020-180239  公開日:2020年11月

    J-GLOBAL

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  • ハイドロゲルおよびその作製方法

    宮田 隆志, 河村 暁文, 稲元 唯乃

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    出願人:学校法人 関西大学

    出願番号:特願2019-085039  出願日:2019年4月

    公開番号:特開2020-180240  公開日:2020年11月

    J-GLOBAL

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  • 正浸透圧利用システムの駆動溶液およびその再生方法

    宮田 隆志, 河村 暁文, 中里 高典

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    出願人:学校法人 関西大学

    出願番号:特願2016-139271  出願日:2016年7月

    公開番号:特開2018-008228  公開日:2018年1月

    特許番号/登録番号:特許第6831554号  登録日:2021年2月 

    J-GLOBAL

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  • 細胞培養用基材、その製造方法、および細胞培養用基材における物性の制御方法

    宮田 隆志, 河村 暁文, 松田 安叶

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    出願人:学校法人 関西大学

    出願番号:特願2016-093920  出願日:2016年5月

    公開番号:特開2017-201891  公開日:2017年11月

    特許番号/登録番号:特許第6718610号  登録日:2020年6月 

    J-GLOBAL

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  • 光修復剤および用途

    宮田 隆志, 河村 暁文, 島井 利樹

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    出願人:日油株式会社

    出願番号:特願2015-142393  出願日:2015年7月

    公開番号:特開2017-023902  公開日:2017年2月

    特許番号/登録番号:特許第6485263号  登録日:2019年3月 

    J-GLOBAL

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  • 多刺激応答性物質およびその形態変更方法ならびに多刺激応答性分子

    宮田 隆志, 河村 暁文, 大熊 幸平

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    出願人:学校法人 関西大学

    出願番号:2014-148499  出願日:2014年7月

    公開番号:2016-23243  公開日:2016年2月

    特許番号/登録番号:特許第6558621号  登録日:2019年7月 

    J-GLOBAL

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  • パターン基材およびその製造方法ならびにパターン形成用基材

    宮田 隆志, 河村 暁文, 秋岡 信博

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    出願人:学校法人 関西大学

    出願番号:2014-039966  出願日:2014年2月

    公開番号:2015-164978  公開日:2015年9月

    J-GLOBAL

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  • ハイドロゲル及びその製造方法

    廣井 良一, 石飛 宏幸, 宮田 隆志, 河村 暁文

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    出願人:大塚化学株式会社, 学校法人 関西大学

    出願番号:2013-138964  出願日:2013年7月

    公開番号:2015-010219  公開日:2015年1月

    特許番号/登録番号:特許第6108990号  登録日:2017年3月 

    J-GLOBAL

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  • 生体材料パターニング用樹脂基材およびその製造方法ならびに生体材料パターニング材およびその製造方法

    宮田 隆志, 河村 暁文, 来田 智行

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    出願人:学校法人 関西大学

    出願番号:2012-256965  出願日:2012年11月

    公開番号:2014-103857  公開日:2014年6月

    特許番号/登録番号:特許第6070106号  登録日:2017年1月 

    J-GLOBAL

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  • 末端にアセタール基とp-ニトロフェニルカルボネート基を有するポリエチレンオキシド誘導体

    原田 敦史, 河村 暁文, 飯島 道弘

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    出願人:公立大学法人大阪府立大学

    出願番号:2005-235669  出願日:2005年8月

    公開番号:2007-51182  公開日:2007年3月

    J-GLOBAL

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受賞

  • 学術賞

    2023年6月   日本接着学会   界面化学的手法を利用した機能性ナノ材料の設計と応用に関する研究

    河村 暁文

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  • 高分子研究奨励賞

    2016年5月   公益社団法人 高分子学会  

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    受賞国:日本国

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  • 日韓バイオマテリアル学会若手研究者交流AWARD

    2014年11月   日本バイオマテリアル学会・韓国バイオマテリアル学会  

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  • 第52回高分子研究発表会(神戸)エクセレントポスター賞

    2006年7月   高分子学会関西支部  

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    受賞国:日本国

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共同研究・競争的資金等の研究課題

  • 血小板ヒッチハイキング型ドラッグデリバリーシステムの創生

    2022年4月 - 2023年3月

    日本私立学校振興・共済事業団  学術研究振興資金 

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  • 難治性固形癌に対する癌抑制型microRNA補充療法の実現に向けた治療戦略の構築

    研究課題/領域番号:21H02992  2021年4月 - 2024年3月

    日本学術振興会  科学研究費助成事業 基盤研究(B)  基盤研究(B)

    谷口 高平, 柴田 雅朗, 林 淳祐, 河村 暁文

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    配分額:17420000円 ( 直接経費:13400000円 、 間接経費:4020000円 )

    本年度は、大腸癌骨盤内再発モデルに対して、化学修飾型miRNA-143をリポフェクションで全身投与(尾静脈投与)する動物実験を中心に進めた。結果として、化学修飾型miRNA投与群で、有意な抗腫瘍効果を認めた。投与後の解析では、腫瘍中のmiRNA-143発現の上昇を認め、組織切片では腫瘍内および辺縁にmiRNA-143の集積を認めた。このことから抗腫瘍効果はmiRNAの投与により生じたということが示唆された。
    さらに抗腫瘍効果の機序を明らかにするため、miRNA投与後の腫瘍切片を用いてプロテオーム解析を実施し、標的遺伝子Xを同定した。miRNA-143とXの関係性および、Xの機能について詳細な検討を進める計画である。
    一方、細胞内還元環境を利用した新たなDDS開発については、ゲル粒子キャリアとプロドラッグ型miRNAの作製を進めた。ゲル粒子キャリアは、予備検討が進み、次年度には細胞導入実験を実施できる状況に至っている。既に導入に使用するmiRNAも選定しており、一部の実験を開始している。プロドラッグ型miRNAの作製に関しては、これまで、鋭敏な抗腫瘍効果は認めることを明らかにしているものの、化学修飾型miRNAの作製に苦戦しているmiRNA-145に照準を絞った。本年度は、化学修飾を付加する位置を決定するために2'-O-メチルを用いた修飾位置の最適化の検討等を実施し、適切な修飾付加の位置が決定しつつある。

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  • 水溶性化合物のシャープな透過制御機能を搭載した温度応答性ナノカプセルの創製

    研究課題/領域番号:21K05202  2021年4月 - 2024年3月

    日本学術振興会  科学研究費助成事業 基盤研究(C)  基盤研究(C)

    河村 暁文

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    配分額:4160000円 ( 直接経費:3200000円 、 間接経費:960000円 )

    【カプセル調製法の確立】双性イオンポリマーと側鎖末端がヒドロキシ基の側鎖オリゴエチレングリコール(OEG)ポリマーとからなるブロック共重合体を合成した。得られたブロック共重合体を水溶性乳化剤として用いて,水/クロロホルム2相系においてW/Oエマルションを形成させた。このエマルションにジビニルスルホンを添加すると,側鎖OEGポリマーブロック間に架橋が導入され,水中においても分散可能なナノカプセルが調製できることがわかった。
    【低温透過型ナノカプセル】双性イオンポリマーブロックとしてポリ(メタクリロイルオキシエチルホスホリルコリン)(PMPC)および下限臨界溶液温度(LCST)型の温度応答性を示す側鎖OEGポリマーブロックとからなるブロック共重合体を合成した。このとき,側鎖OEGの鎖長が2と5のモノマーを共重合することにより,40℃で相転移するブロック共重合体を得た。得られたブロック共重合体は水/クロロホルム2相系においてW/Oエマルションを形成するとともに,ジビニルスルホンによる架橋によりナノカプセルを形成した。得られたナノカプセル分散液は昇温に伴って白濁し,温度応答性を示すことがわかった。
    【高温透過型ナノカプセル】上限臨界溶液温度(UCST)型の温度応答性を示すアンモニウムサルフェート型の双性イオンポリマーブロックと側鎖OEGポリマーブロックとからなるブロック共重合体を合成した。得られたブロック共重合体は,生理的イオン強度環境下において38℃付近を境に疎水性から親水性へと相転移することがわかった。

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  • 高防汚性と易原料化とを兼備する双性イオン型PETの開発

    2020年4月 - 2022年3月

    独立行政法人環境再生保全機構  環境研究総合推進費 

    河村 暁文

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    担当区分:研究代表者  資金種別:競争的資金

    配分額:14580000円 ( 直接経費:11217000円 、 間接経費:3363000円 )

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  • 水溶性物質の高封入効率と刺激応答放出とを可能にする両親媒性ナノカプセルの設計

    2020年4月 - 2021年3月

    公益財団法人 池谷科学技術振興財団  単年度研究助成

    河村 暁文

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    担当区分:研究代表者  資金種別:競争的資金

    配分額:1000000円

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  • 高感度診断システムの構築を目指した酵素カスケード反応場としての高分子ナノカプセルの創製

    2017年 - 2018年

    公益財団法人高橋産業経済研究財団 

    河村 暁文

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    担当区分:研究代表者  資金種別:競争的資金

    配分額:2000000円 ( 直接経費:2000000円 )

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  • 細胞内環境を認識する多刺激応答性ゲル微粒子によるナノトランスポーターの創製

    研究課題/領域番号:15K17912  2015年4月 - 2017年3月

    日本学術振興会  科学研究費助成事業 若手研究(B)  若手研究(B)

    河村 暁文

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    担当区分:研究代表者  資金種別:競争的資金

    配分額:4290000円 ( 直接経費:3300000円 、 間接経費:990000円 )

    細胞内環境を認識して薬物を放出するナノトランスポーターの創製を目的として,酸性かつ還元環境において膨潤する二重刺激応答性ゲル微粒子を設計・合成した。得られたゲル微粒子は,酸性かつ還元環境において劇的に膨潤した。また,その細胞内動態を観察したところ,ゲル微粒子の細胞毒性は低く,エンドサイトーシス経路により細胞内に取り込まれることがわかった。さらにゲル微粒子内への抗がん剤やオリゴ核酸の内包プロトコールを確立し,ゲル微粒子からの薬物放出挙動を評価したところ,酸性かつ還元環境下において薬物の放出が促進されることがわかった。このような二重刺激応答性ゲル微粒子はナノトランスポーターとして有用である。

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  • コロイドフォトニック結晶の構築を指向した分子応答性高分子ナノ粒子の創製

    2015年

    公益財団法人 花王芸術・科学財団 

    河村 暁文

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    担当区分:研究代表者  資金種別:競争的資金

    配分額:1000000円 ( 直接経費:1000000円 )

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  • 物質拡散ベクトルを考慮したナノ微粒子内酵素二段階反応システムの構築

    2007年

    財団法人日本科学協会  笹川科学研究助成 

    河村 暁文

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    担当区分:研究代表者  資金種別:競争的資金

    配分額:700000円 ( 直接経費:700000円 )

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担当経験のある科目(授業)

  • 化学を学ぶ(演習含)(基礎化学1)

    2017年4月 - 現在 機関名:関西大学

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  • バイオインスパイアード化学特論

    2017年4月 - 現在 機関名:関西大学

     詳細を見る

  • 化学実験

    2012年4月 - 現在 機関名:関西大学

     詳細を見る

  • 基礎化学実験

    2012年4月 - 2021年9月 機関名:関西大学

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社会貢献活動

  • IUMRS-ICAM2017 Symposium B-4 Correspondence Organizer

    2017年

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  • 第84回高分子若手研究会【関西】 世話人

    2015年

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