Updated on 2025/06/23

写真a

 
SAKAI, Kiyotaka
 
Affiliation
Faculty of Science and Engineering
Job title
Professor Emeritus
Degree
(BLANK) ( Waseda University )

Education Background

  •  
    -
    1965

    Waseda University   School of Science and Engineering  

  •  
    -
    1965

    Waseda University   Faculty of Science and Engineering   Department of Chemical Engineering  

Committee Memberships

  • 1999
    -
     

    化学工学会  評議員

  • 1996
    -
     

    日本医工学治療学会  副理事長

  • 1993
    -
     

    日本膜学会  理事

  • 1992
    -
     

    日本臨床工学技師会  顧問

  • 1982
    -
     

    日本人工臓器学会  評議員

  •  
     
     

    日本エム・イー学会  評議員

  •  
     
     

    日本血液代替物学会  評議員

▼display all

Professional Memberships

  •  
     
     

    ISAO (International Society for Artificial Organs)

  •  
     
     

    EDTA (European Dialysis and Transplantation Association)

  •  
     
     

    ASAIO (American Society for Artificial Internal Organs)

  •  
     
     

    AIChE (American Institute of Chemical Engineers)

  •  
     
     

    日本医科器械学会

  •  
     
     

    日本生物工学会

  •  
     
     

    日本腎臓学会

  •  
     
     

    日本アフェレーシス学会

  •  
     
     

    日本エム・イー学会

  •  
     
     

    Internatinal Society for Artificial Orgaus

  •  
     
     

    高分子学会

  •  
     
     

    日本化学会

  •  
     
     

    日本血液代替物学会

  •  
     
     

    日本臨床工学技師会

  •  
     
     

    American Society for Artificial Internal Organs

  •  
     
     

    日本透析医学会

  •  
     
     

    日本アフェレシス学会

  •  
     
     

    日本医工学治療学会

  •  
     
     

    European Dialysis and Transplant Asociation

  •  
     
     

    化学工学会

  •  
     
     

    日本膜学会

  •  
     
     

    American Institute of Chemical Engineers

  •  
     
     

    日本人工臓器学会

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Research Areas

  • Biomaterials / Biomedical engineering

Research Interests

  • 反応・分離工学

  • 生物・生体工学

  • Chemical Engineering

  • Biomedical Engineering

  • Biochemical Engineering

Awards

  • 化学工学会学会賞

    1999  

  • 日本人工臓器学会論文賞

    1998  

  • 日本人工臓器学会論文賞

    1997  

  • 日本人工臓器学会論文賞

    1995  

  • 日本医科器械学会著述賞

    1994  

  • 化学工学会研究賞

    1991  

▼display all

 

Books and Other Publications

  • 透析膜の生体適合性~透析膜の素材はいかに関与するか~

    東京医学社  2010

  • 血液浄化療法2009

    東京医学社  2008

  • 生命・医療・福祉ハンドブック

    コロナ社  2007

  • 機械工学便覧 デザイン編beta8(生体工学)

    丸善  2007

  • Pro medica 医学大辞典 19版 CD-ROM

    南山堂  2007

  • 医学大辞典 19版

    南山堂  2006

  • 最先端の機能膜技術ー未来の膜技術を展望するー

    シーエムシー出版  2005

  • 21世紀の化学シリーズ14 化学工学

    朝倉書店  2005

  • 最近の化学工学56 先端医療における化学工学

    化学工学会  2004

  • 血液浄化療法ハンドブック

    協同医書出版社  2004

  • Reflexive Polymers and Hydrogels --Understanding and Designing Fast Responsive Polymeric--

    CRC Press  2004

  • Bio-mechanisms of Swimming and Flying

    Springer  2004

  • Reflexive Polymers and Hydrogels --Understanding and Designing Fast Responsive Polymeric--

    CRC Press  2004

  • Bio-mechanisms of Swimming and Flying

    Springer  2004

  • ME教科書シリーズ 人工臓器(II)

    コロナ社  2003

  • ライフケアと高分子

    エヌ・ティー・エス  2002

  • バイオミメティックスハンドブック

    エヌ・ティー・エス  2000

  • 吸着技術便覧ーープロセス・材料・設計ーー

    エヌ・ティー・エス  1999

  • 化学工学便覧

    丸善  1999

  • Newtonムック 21世紀を切り開く先端医療 バイオメディカル・エンジニアリング入門

    ニュートンプレス  1999

  • ME用語辞典

    コロナ社  1999

  • 血液浄化療法ハンドブック

    協同医書出版社  1998

  • Heart Replacement, Artificial Heart 6

    Springer  1998

  • バイオマテリアルと生体(副作用と安全性)

    中山書店  1998

  • Biorelated Polymers and Gels

    Academic Press  1998

  • Heart Replacement, Artificial Heart 6

    Springer  1998

  • Biorelated Polymers and Gels

    Academic Press  1998

  • 高純度化技術体系第2巻分離技術

    フジ・テクノシステム  1997

  • 最近の化学工学49「膜技術の動向と将来展望」

    化学工業社  1997

  • 化学工学シンポジウムシリーズ58 バイオメディカル研究の動向と工学的課題

    化学工学会  1997

  • ゲルハンドブック

    エヌ・ティー・エス  1997

  • 血漿浄化療法

    医学書院  1996

  • 化学工学シンポジウムシリーズ55 治療と診断のシステム

    化学工学会  1996

  • Heart Replacement, Artificial Heart 5

    Springer  1996

  • Heart Replacement, Artificial Heart 5

    Springer  1996

  • メディカルテクノロジーへの招待

    培風館  1995

  • Advanced Biomaterials in Biomedical Engineering and Drug Delivery Systems

    Springer-Verlag Tokyo  1995

  • Advanced Biomaterials in Biomedical Engineering and Drug Delivery Systems

    Springer-Verlag Tokyo  1995

  • 膜学実験シリーズ第2巻 生体機能類似膜編

    日本膜学会  1994

  • 化学工学の進歩28 流体・粒子系分離

    槙書店  1994

  • 化学工学シンポジウムシリーズ43 制御放出技術

    化学工学会  1994

  • 化学工学シンポジウムシリーズ41 膜工学の新しい挑戦ー1994

    化学工学会  1994

  • The Expanding World of Chemical Engineering

    Gordon and Breach Science Publishers  1994

  • Better Living Through Innovative Biochemical Engineering

    National University of Singapore  1994

  • Advanced Materials '93, II / A: Biomaterials, Organic and Intelligent Materials

    Elsevier Science B.V.  1994

  • The Expanding World of Chemical Engineering

    Gordon and Breach Science Publishers  1994

  • Better Living Through Innovative Biochemical Engineering

    National University of Singapore  1994

  • Advanced Materials '93, II / A: Biomaterials, Organic and Intelligent Materials

    Elsevier Science B.V.  1994

  • 膜分離プロセスの理論と設計

    アイピーシー  1993

  • 分離科学ハンドブック

    共立出版  1993

  • ME早わかりQ&A 6 血液透析・血液濾過・血液灌流(第3刷1993年9月20日)

    南江堂  1993

  • 人工臓器1993(Artificial Organs '93 Annual Review)

    中山書店  1993

  • 化学工学と人工臓器

    共立出版  1993

  • おもしろい膜のはなし

    日刊工業新聞社  1992

  • Biochemical Engineering for 2001

    Springer-Verlag  1992

  • Biochemical Engineering for 2001

    Springer-Verlag  1992

  • 膜処理技術大系 上巻

    フジ・テクノシステム  1991

  • 日本臨床 別冊 血液浄化療法(上巻)

    日本臨床  1991

  • バイオメカニクスシリーズ 生体力学

    オーム社  1991

  • Polymer Gels

    Plenum Press  1991

  • 人工臓器用語解説集

    金原出版  1991

  • Polymer Gels

    Plenum Press  1991

  • 体外免疫調節

    日本メディカルセンター  1990

  • 血液浄化(医工学治療機器マニュアル1)

    金原出版  1990

  • WIBA'90 医療・福祉・保健の総合年鑑

    日本医療企画  1990

  • Apheresis

    Alan R. Liss, Inc.  1990

  • Apheresis

    Alan R. Liss, Inc.  1990

  • 膜分離技術マニュアル

    アイピーシー  1989

  • 透析スタッフのための血液浄化の基礎

    アイピーシー  1989

  • 最近の化学工学 「膜分離工学ーその現状と工業的応用ー」

    化学工業社  1989

  • 日本機械学会 バイオテクノロジー・メディカルエンジニアリング

    丸善  1988

  • 最新高分子材料・技術総覧

    産業技術サービスセンター  1988

  • 化学工学便覧

    丸善  1988

  • 人工臓器用語集

    金原出版  1987

  • 最新の人工臓器技術と今後の展望

    アイピーシー  1987

  • 高度膜分離技術ハンドブック

    サイエンスフォーラム  1987

  • ケミカルエンジニアリングのすすめ

    共立出版  1987

  • Progress in Artificial Organs-1985

    ISAO Press  1986

  • Proceedings of World Congress � of Chemical Engineering

    The Society of Chemical Engineers、 Japan  1986

  • Progress in Artificial Organs-1985

    ISAO Press  1986

  • Proceedings of World Congress � of Chemical Engineering

    The Society of Chemical Engineers、 Japan  1986

  • 臨床液体クロマトグラフィー

    講談社サイエンティフィック  1984

  • 臨床MEハンドブック

    コロナ社/医学書院  1984

  • 臨床検査MOOK No.16 腎透析と臨床検査

    金原出版  1983

  • Progress in Artificial Organs-1983

    ISAO Press  1983

  • Progress in Artificial Organs-1983

    ISAO Press  1983

  • 最近の化学工学「膜利用技術」

    学術談刊行センタ-/学会出版センタ-  1982

  • 維持透析「雑誌日本臨床, Vol.39(特別号)No.474 」

    日本臨床社  1981

  • 化学ハンドブック

    オ-ム社  1978

  • 化学工学の進歩4 高温工学

    日刊工業新聞社  1970

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Presentations

  • 市販透析膜への吸着タンパク質の分析

    日本医工学治療学会 第26回学術大会 / 都市センター 

    Presentation date: 2010

  • 透析膜における溶質透過のシミュレーション解析

    日本医工学治療学会 第26回学術大会 / 都市センター 

    Presentation date: 2010

  • セルローストリアセテート中空糸透析膜の内部構造

    日本医工学治療学会 第26回学術大会 / 都市センター 

    Presentation date: 2010

  • 血中抗体濃度測定を目指した蛍光増強免疫測定法の改良

    日本医工学治療学会 第26回学術大会 / 都市センター 

    Presentation date: 2010

  • フロー式蛍光増強免疫測定法による免疫グロブリンG(IgG)の繰り返し測定の検証

    日本医工学治療学会 第26回学術大会 / 都市センター 

    Presentation date: 2010

  • 対向流増幅効果を利用した人工尿細管システムの開発

    日本医工学治療学会 第26回学術大会 / 都市センター 

    Presentation date: 2010

  • 疑似腹膜中皮モデルを用いた腹膜障害へのHGFの効果

    日本医工学治療学会 第26回学術大会 / 都市センター 

    Presentation date: 2010

  • 人工肺モジュールにおける酸素移動のシミュレーション解析

    日本医工学治療学会 第26回学術大会 / 都市センター 

    Presentation date: 2010

  • 透析患者の血中NO濃度リアルタイム測定装置の開発

    日本医工学治療学会 第26回学術大会 / 都市センター 

    Presentation date: 2010

  • 超音波ドップラー法によるAPS-15SAの内部濾過流量経時変化の推定

    日本医工学治療学会 第26回学術大会 / 都市センター 

    Presentation date: 2010

  • 血液側および透析液側流動を考慮した高性能中空糸型透析器の設計

    日本医工学治療学会 第26回学術大会 / 都市センター 

    Presentation date: 2010

  • リユース処理が透析膜表面に与える影響

    日本医工学治療学会 第26回学術大会 / 都市センター 

    Presentation date: 2010

  • 広範囲分子量におけるPVP溶出の定量的評価

    日本医工学治療学会 第26回学術大会 / 都市センター 

    Presentation date: 2010

  • 免疫グロブリンG(IgG)の繰り返し測定が可能なフロー式免疫走測定法の開発

    第12回 化学工学会学生発表会 東京大会 / 芝浦工業大学豊洲キャンパス 

    Presentation date: 2010

  • 透析膜における溶質透過の可視化(続)

    第12回 化学工学会学生発表会 東京大会 / 芝浦工業大学豊洲キャンパス 

    Presentation date: 2010

  • オクタノール2相系の電位振動に同期した界面の流れの観察

    化学工学会 第75年会 / 鹿児島大学 

    Presentation date: 2010

  • 保管期間が異なる合成高分子透析膜からのPVP溶出特性

    ハイパフォーマンス・メンブレン(第25回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2010

  • 親水化剤配合率とγ線総吸収量の違いがPSfフィルム表面のタンパク質吸着に与える影響

    ハイパフォーマンス・メンブレン(第25回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2010

  • 近接場顕微赤外分光法による透析膜内表面のアルブミン吸着層の解析

    ハイパフォーマンス・メンブレン(第25回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2010

  • ずり応力を負荷された透析膜表面の粗度・硬度およびPVP溶出に異なる滅菌法が与える影響

    ハイパフォーマンス・メンブレン(第25回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2010

  • PSf透析膜表面におけるPVP分布のNFIR解析

    ハイパフォーマンス・メンブレン(第25回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2010

  • セルローストリアセテート中空糸透析膜の構造解析

    ハイパフォーマンス・メンブレン(第25回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2010

  • 命を繋ぐ細い糸:中空糸を使った人工臓器

    化学工学会関東支部 第14回高校生のための現代寺小屋講座 / 芝浦工業大学 豊洲キャンパス 

    Presentation date: 2009

  • EVAL膜とPVP配合合成高分子膜のHAS吸着力の比較

    ハイパフォーマンスメンブレン(第24回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2009

  • 免疫速度における蛍光増強の血漿中IgG濃度依存性

    第48回日本生体医工学大会 / タワーホール船堀 

    Presentation date: 2009

  • Temperature-controlled intracellular uptake of thermoresponsive polymeric micelles

    The 14th International Symposium on Recent Advances in Drug Delivery Systems / the Sheraton Hotel, Salt Lake City, Utah, USA 

    Presentation date: 2009

  • 命を繋ぐ細い糸:中空糸を使った人工臓器 腎臓のリリーフ:人工腎臓

    化学工学会関東支部 第14回高校生のための現代寺小屋講座 / 芝浦工業大学 豊洲キャンパス 

    Presentation date: 2009

  • 血液透析濾過(HDF)透析器の設計に関する基礎的検討

    ハイパフォーマンスメンブレン(第24回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2009

  • EVAL膜とPVP配合合成高分子膜のHSA吸着力の比較

    ハイパフォーマンスメンブレン(第24回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2009

  • 透析膜における溶質透過の可視化

    ハイパフォーマンスメンブレン(第24回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2009

  • PVP含有率の異なるPEPA膜からのPVP溶出特性

    ハイパフォーマンスメンブレン(第24回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2009

  • 近接場顕微赤外分光法による透析膜表面におけるポリビニルピロリドン(PVP)分子の分析

    ハイパフォーマンスメンブレン(第24回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2009

  • APS-15SAの性能の経時変化に及ぼす血液流量および濾液流量の影響

    ハイパフォーマンスメンブレン(第24回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2009

  • テーパー構造における透析流の解析

    ハイパフォーマンスメンブレン(第24回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2009

  • 血液透析膜の内表面特性がヒト血清アルブミン吸着力に及ぼす影響

    化学工学会 第74年会 / 横浜国立大学 

    Presentation date: 2009

  • 新型血液透析器における透析液流動の無次元相関式による評価

    化学工学会 第74年会 / 横浜国立大学 

    Presentation date: 2009

  • オクタノール電気振動系における界面吸着

    化学工学会 第74年会 / 横浜国立大学 

    Presentation date: 2009

  • バイオイメージングを指向した温度応答性ガラス表面の作製

    日本医工学治療学会 第25回学術大会 / 大阪国際会議場 

    Presentation date: 2009

  • 温度スイッチによる高分子型薬物キャリアの細胞内移行制御

    日本医工学治療学会 第25回学術大会 / 大阪国際会議場 

    Presentation date: 2009

  • ウシ血漿中IgGによる蛍光標識プロテインAの蛍光増強

    日本医工学治療学会 第25回学術大会 / 大阪国際会議場 

    Presentation date: 2009

  • 透析液流動の改善に効果的な透析器テーパ部の作製とその評価

    日本医工学治療学会 第25回学術大会 / 大阪国際会議場 

    Presentation date: 2009

  • 免疫測定における蛍光増強の血漿中IgG濃度依存性

    第48回日本生体医工学会大会 / タワーホール船堀 

    Presentation date: 2009

  • ずり応力負荷による親水化剤溶出が透析膜表面特性に与える影響

    日本膜学会第31年会 / 東京理科大学 森戸記念館 

    Presentation date: 2009

  • 透析膜における溶質透過挙動の可視化

    日本膜学会第31年会 / 東京理科大学 森戸記念館 

    Presentation date: 2009

  • 透析膜のPVP溶出特性

    日本透析医学会学術集会・総会(第54回) / パシフィコ横浜 

    Presentation date: 2009

  • 過剰なγ線照射が湿潤透析膜表面特性に与える影響

    日本透析医学会学術集会・総会(第54回) / パシフィコ横浜 

    Presentation date: 2009

  • ANSYS-CFXを用いた中空糸型透析器内における透析液流動の評価

    日本透析医学会学術集会・総会(第54回) / パシフィコ横浜 

    Presentation date: 2009

  • 血液透析膜素材がリンパ球機能へ及ぼす影響のex vivo評価

    日本透析医学会学術集会・総会(第54回) / パシフィコ横浜 

    Presentation date: 2009

  • 学生賞 奨励(テーパ部を改良したモデル透析器の試作と透析液流動の可視化)

    化学工学会米沢大会2009(3支部合同大会) / 山形大学工学部 

    Presentation date: 2009

  • テーパ部を改良したモデル透析器の試作と透析液流動の可視化

    化学工学会米沢大会2009(3支部合同大会) / 山形大学工学部 

    Presentation date: 2009

  • 「元気に長生きするための透析」~透析器の性能向上のための工夫~

    江戸川区 腎機能障害者向け講演会 / タワーホール船堀 

    Presentation date: 2009

  • 親水化剤配合率の違いが透析膜表面のタンパク質吸着に与える影響

    化学工学会 第41回秋季大会 / 広島大学 東広島キャンパス 

    Presentation date: 2009

  • 透析膜からの親水化剤溶出特性

    化学工学会 第41回秋季大会 / 広島大学 東広島キャンパス 

    Presentation date: 2009

  • ずり応力負荷に伴う透析膜表面PVPの溶出と表面特性の変化

    化学工学会 第41回秋季大会 / 広島大学 東広島キャンパス 

    Presentation date: 2009

  • 透析器形状が透析液流動と物質移動に及ぼす影響

    化学工学会 第41回秋季大会 / 広島大学 東広島キャンパス 

    Presentation date: 2009

  • 血液透析器における流動と物質移動のシミュレーション解析

    化学工学会 第41回秋季大会 / 広島大学 東広島キャンパス 

    Presentation date: 2009

  • 急速麻酔導入時の薬物動態解析

    化学工学会 第41回秋季大会 / 広島大学 東広島キャンパス 

    Presentation date: 2009

  • 直腸温の連続測定による死後経過時間の推算

    化学工学会 第41回秋季大会 / 広島大学 東広島キャンパス 

    Presentation date: 2009

  • 生体肺内空気流動状態の可視化

    化学工学会 第41回秋季大会 / 広島大学 東広島キャンパス 

    Presentation date: 2009

  • Determination of immunoglobulin G by fluorescence enhancement using fluorescent-labeled protein A

    World Congress 2009 Medical Physics and Biomedical Engineering / International Congress Center, Munich, Germany 

    Presentation date: 2009

  • Determination of polyvinylpyrrolidone elution from synthetic polymer dialysis membranes

    World Congress 2009 Medical Physics and Biomedical Engineering / International Congress Center, Munich, Germany 

    Presentation date: 2009

  • Dialysis fluid flow in a hollow-fiber dialyzer and its effects on dialysis performance

    World Congress 2009 Medical Physics and Biomedical Engineering / International Congress Center, Munich, Germany 

    Presentation date: 2009

  • 温度応答性ブロックコポリマーを用いた細胞内移行型ナノミセル

    第58回高分子学会年次大会 / 神戸国際会議場 

    Presentation date: 2009

  • 局所加温応答能を有する細胞内薬物デリバリーシステムの構築

    第25回日本DDS学会 / 東京ドームホテル 

    Presentation date: 2009

  • 対向流増幅効果を利用した人工尿細管システムにおいて水回収方法の違いが尿素濃縮率に及ぼす影響

    第18回日本次世代人工腎臓研究会 / 全社協 灘尾ホール 

    Presentation date: 2009

  • 救急医療のための装置開発

    日本人工臓器学会大会(第47回) / 朱鷺メッセ 新潟コンベンションセンター 

    Presentation date: 2009

  • 化学発光を用いた血中NO濃度測定装置の開発

    日本人工臓器学会大会(第47回) / 朱鷺メッセ 新潟コンベンションセンター 

    Presentation date: 2009

  • 透析液流動改善のためにテーパ部を改良した透析器の開発

    日本人工臓器学会大会(第47回) / 朱鷺メッセ 新潟コンベンションセンター 

    Presentation date: 2009

  • ずり応力負荷による透析膜からのPVP溶出と膜表面構造の変化

    日本人工臓器学会大会(第47回) / 朱鷺メッセ 新潟コンベンションセンター 

    Presentation date: 2009

  • 最新透析膜のPVP溶出特性

    日本人工臓器学会大会(第47回) / 朱鷺メッセ 新潟コンベンションセンター 

    Presentation date: 2009

  • 日本人工臓器学会論文賞

    日本人工臓器学会大会(第47回) / 朱鷺メッセ 新潟コンベンションセンター 

    Presentation date: 2009

  • Thermoresponsive polymeric micelles as thermally modulated intracellular delivery tools

    8th FBPS2009 (International Symposium on Prontiers in Biomedical Polymers) / Toray Human Resaurces Development Center 

    Presentation date: 2009

  • 湿潤透析膜表面のナノキャラクタリゼーション

    INCHEM TOKYO 2009 / 東京ビックサイト 

    Presentation date: 2009

  • 近接場顕微赤外分光法による透析膜表面のポリビニルピロリドン分布解析

    膜シンポジウム2009 / 広島大学医学部応仁会館大会議室 

    Presentation date: 2009

  • Temperature-controlled intracellular uptake of thermoresponsive polymeric micelles

    The 14th International Symposium on Recent Advances in Drug Delivery Systems / the Sheraton Hotel, Salt Lake City, Utah, USA 

    Presentation date: 2009

  • Determination of immunoglobulin G by fluorescence enhancement using fluorescent-labeled protein A

    World Congress 2009 Medical Physics and Biomedical Engineering / International Congress Center, Munich, Germany 

    Presentation date: 2009

  • Determination of polyvinylpyrrolidone elution from synthetic polymer dialysis membranes

    World Congress 2009 Medical Physics and Biomedical Engineering / International Congress Center, Munich, Germany 

    Presentation date: 2009

  • Dialysis fluid flow in a hollow-fiber dialyzer and its effects on dialysis performance

    World Congress 2009 Medical Physics and Biomedical Engineering / International Congress Center, Munich, Germany 

    Presentation date: 2009

  • Thermoresponsive polymeric micelles as thermally modulated intracellular delivery tools

    8th FBPS2009 (International Symposium on Prontiers in Biomedical Polymers) / Toray Human Resaurces Development Center 

    Presentation date: 2009

  • 膜構造制御によるアルブミン漏出の抑制

    ハイパフォーマンスメンブレン(第23回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2008

  • 原子間力顕微鏡による血液透析膜の生体適合性の評価

    ハイパフォーマンスメンブレン(第23回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2008

  • 透析膜へのずり応力負荷が親水化剤溶出および表面構造に与える影響

    ハイパフォーマンスメンブレン(第23回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2008

  • 透析膜表面PVP減少が表面特性に与える影響

    ハイパフォーマンスメンブレン(第23回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2008

  • 最新の合成高分子系血液透析膜の内表面特性評価

    ハイパフォーマンスメンブレン(第23回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2008

  • 新型血液透析器における透析液側流動の無次元相関式による評価

    ハイパフォーマンスメンブレン(第23回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2008

  • 透析器ハウジング形状が透析液流動に及ぼす影響

    ハイパフォーマンスメンブレン(第23回) / 日本消防会館(ニッショーホール) 

    Presentation date: 2008

  • 水/オクタノール2相振動系における液滴の揺れ

    化学工学会 第73年会 / 静岡大学 浜松キャンパス 

    Presentation date: 2008

  • 吸入麻酔導入期における体内麻酔薬動態シミュレーション

    化学工学会 第73年会 / 静岡大学 浜松キャンパス 

    Presentation date: 2008

  • 人工鰓システム実用化に向けた性能評価

    化学工学会 第73年会 / 静岡大学 浜松キャンパス 

    Presentation date: 2008

  • 透析膜内表面特性のナノレベル評価の必要性

    日本医工学治療学会 第24回学術大会 / 幕張メッセ国際会議場 

    Presentation date: 2008

  • 血中低分子ヘパリン測定のためのプロタミン固定化ガラスの作成

    日本医工学治療学会 第24回学術大会 / 幕張メッセ国際会議場 

    Presentation date: 2008

  • 透析膜内表面からPVP溶出

    日本医工学治療学会 第24回学術大会 / 幕張メッセ国際会議場 

    Presentation date: 2008

  • 新しい人工腎臓の血液透析膜に対するHSA吸着力の評価

    日本医工学治療学会 第24回学術大会 / 幕張メッセ国際会議場 

    Presentation date: 2008

  • 人工肺における血液出口ポート位置と構造が血液流動に及ぼす影響

    日本医工学治療学会 第24回学術大会 / 幕張メッセ国際会議場 

    Presentation date: 2008

  • クレアチニン濃度に応答する拡散透過制御膜の開発

    日本医工学治療学会 第24回学術大会 / 幕張メッセ国際会議場 

    Presentation date: 2008

  • 透析器ジャケットのテーパ形状が透析液流動に及ぼす影響

    日本医工学治療学会 第24回学術大会 / 幕張メッセ国際会議場 

    Presentation date: 2008

  • 無次元相関式を用いた血液透析器の透析側流動状態の評価

    日本医工学治療学会 第24回学術大会 / 幕張メッセ国際会議場 

    Presentation date: 2008

  • Development of a novel device for measuring O2- concentration generated by direct contact of dialysys membrane with blood

    XLV ERA-EDTA Congress / Stockholm International Fairs and Congess Center, Sweden 

    Presentation date: 2008

  • 透析膜表面タンパク質吸着が透析膜透水性に及ぼす影響

    日本膜学会第30年会 / 東京理科大学 

    Presentation date: 2008

  • Effect of container material on electrical oscillation in water/octanol 2-phase system

    213th ECS meeting / Phoenix Convention Cneter, Phoniix, AZ, USA 

    Presentation date: 2008

  • 蛍光増強免疫測定に影響する因子の検討

    第47回 日本生体医工学会大会 / 神戸国際会議場 

    Presentation date: 2008

  • 酸素濃縮器に用いる温度応答性ガスキャリア液の開発

    第47回 日本生体医工学会大会 / 神戸国際会議場 

    Presentation date: 2008

  • Optimum structure design of blood outlet port(BOP) in a membrane oxygenator(MO)

    American Society for Artificial Internal Organs (ASAIO) 54th Annual Conference / San Francisco, USA 

    Presentation date: 2008

  • ASAIO Fellowship "Technical characterization of dialysis fluid flow and mass transfer rate of newly-developed dialyzers(NDD)"

    American Society for Artificial Internal Organs (ASAIO) 54th Annual Conference / San Francisco, USA 

    Presentation date: 2008

  • Technical characterization of dialysis fluid flow and mass transfer rate of newly-developed dialyzers(NDD)

    American Society for Artificial Internal Organs (ASAIO) 54th Annual Conference / San Francisco, USA 

    Presentation date: 2008

  • ASAIO Fellowship "Surface properties of dialysis membranes and their effects on biocompatibility"

    American Society for Artificial Internal Organs (ASAIO) 54th Annual Conference / San Francisco, USA 

    Presentation date: 2008

  • Surface properties of dialysis membranes and their effects on biocompatibility

    American Society for Artificial Internal Organs (ASAIO) 54th Annual Conference / San Francisco, USA 

    Presentation date: 2008

  • コンピュータシミュレーションによる透析器テーパ構造の至適設計

    日本透析医学会学術集会・総会(第53回) / 神戸コンベンションセンター 

    Presentation date: 2008

  • タンパク質吸着に伴う透析膜表面構造変化が濾過係数に及ぼす影響

    日本透析医学会学術集会・総会(第53回) / 神戸コンベンションセンター 

    Presentation date: 2008

  • 透析膜の生体適合性を示す指標としてのHSA吸着力

    日本透析医学会学術集会・総会(第53回) / 神戸コンベンションセンター 

    Presentation date: 2008

  • 小型O2-濃度測定装置の開発

    日本透析医学会学術集会・総会(第53回) / 神戸コンベンションセンター 

    Presentation date: 2008

  • ワークショップ「新しい医療機器をわが国から生み出すためには」~(財)化学技術戦略推進機構での調査や解析などをもとにした報告と提言~

    日本透析医学会学術集会・総会(第53回) / 神戸コンベンションセンター 

    Presentation date: 2008

  • 血液浄化法の新技術

    日本透析医学会学術集会・総会(第53回) / 神戸コンベンションセンター 

    Presentation date: 2008

  • 温度変化を利用した高分子ミセルの細胞内移動メカニズムの解析

    第24回日本DDS学会 / 六本木アカデミーヒルズ40 

    Presentation date: 2008

  • Characterization of wet dialysis membrane surface by atmic force microscopy

    ICOM 2008 (The 2008 International Congress on Membranes and Membrane Processes) / Hawaii, USA 

    Presentation date: 2008

  • 温度応答性高分子ミセルの細胞内移動メカニズムの解析

    第37回医用高分子シンポジウム / 東京医科歯科大学 

    Presentation date: 2008

  • 細胞内デリバリーを目的とした温度応答型薬物キャリアシステムの構造

    化学工学会 第40回秋季大会 / 東北大学 

    Presentation date: 2008

  • 膜構造が溶質透過能に及ぼす影響

    化学工学会 第40回秋季大会 / 東北大学 

    Presentation date: 2008

  • 温度制御型人工鰓システムの開発と実測

    化学工学会 第40回秋季大会 / 東北大学 

    Presentation date: 2008

  • コンピュータシミュレーションによる外部灌流膜型人工肺の物質移動解析

    化学工学会 第40回秋季大会 / 東北大学 

    Presentation date: 2008

  • 蛍光増強免疫測定に及ぼすβ2-ミクログロブリンの影響

    化学工学会 第40回秋季大会 / 東北大学 

    Presentation date: 2008

  • Effects of taper structure of dialyzer jacket on dialysis fluid flow

    XXXV ESAO Congress / geneva, Switerland 

    Presentation date: 2008

  • 湿潤透析膜表面ナノキャラクタリゼーションによる生体適合性評価

    日本人工臓器学会大会(第46回) / 六本木アカデミーヒルズ40階 

    Presentation date: 2008

  • Characterization of hemodialysis membrane Surface by atmic force microscopy

    The 14th Symposium of Young Asian Biochemical Engineers' Community / Shibaura Institute of Technology 

    Presentation date: 2008

  • 温度応答性ガラス表面を構築した細胞培養基材の開発

    日本医工学治療学会 第24回学術大会 / 幕張メッセ国際会議場 

    Presentation date: 2008

  • 相転移現象に伴う温度応答性高分子ミセルの細胞内移行メカニズムの解析

    第30回 日本バイオマテリアル学会大会 / 東京大学 

    Presentation date: 2008

  • 合成高分子透析膜からPVP溶出特性の定量的評価

    日本人工臓器学会大会(第46回) / 六本木アカデミーヒルズ40階 

    Presentation date: 2008

  • 透析膜内表面のタンパク質被覆によるHSA吸着力の経時的変化

    日本人工臓器学会大会(第46回) / 六本木アカデミーヒルズ40階 

    Presentation date: 2008

  • ずり応力負荷が透析膜表面特性に与える影響

    日本人工臓器学会大会(第46回) / 六本木アカデミーヒルズ40階 

    Presentation date: 2008

  • テーパーを持つ透析器の透析流の解析

    日本人工臓器学会大会(第46回) / 六本木アカデミーヒルズ40階 

    Presentation date: 2008

  • 人工肺モジュールの血液出口位置と構造が血液流動および酸素移動速度に与える影響

    日本人工臓器学会大会(第46回) / 六本木アカデミーヒルズ40階 

    Presentation date: 2008

  • 湿潤透析膜表面ナノキャラクタリゼーションによる生体適合性評価

    日本次世代人工腎臓研究会(第17回) / 六本木アカデミーヒルズ40階 

    Presentation date: 2008

  • Characterization of hemodialysis membrane surface by atomic force microscopy

    The 14th Symposium of Young Asian Biochemical Engineers' Community / Shibaura Institute of Technology 

    Presentation date: 2008

  • Development of a novel device for measuring O2- concentration generated by direct contact of dialysys membrane with blood

    XLV ERA-EDTA Congress / Stockholm International Fairs and Congess Center, Sweden 

    Presentation date: 2008

  • Effect of container material on electrical oscillation in water/octanol 2-phase system

    213th ECS meeting / Phoenix Convention Cneter, Phoniix, AZ, USA 

    Presentation date: 2008

  • Optimum structure design of blood outlet port(BOP) in a membrane oxygenator(MO)

    American Society for Artificial Internal Organs (ASAIO) 54th Annual Conference / San Francisco, USA 

    Presentation date: 2008

  • ASAIO Fellowship "Technical characterization of dialysis fluid flow and mass transfer rate of newly-developed dialyzers(NDD)"

    American Society for Artificial Internal Organs (ASAIO) 54th Annual Conference / San Francisco, USA 

    Presentation date: 2008

  • Technical characterization of dialysis fluid flow and mass transfer rate of newly-developed dialyzers(NDD)

    American Society for Artificial Internal Organs (ASAIO) 54th Annual Conference / San Francisco, USA 

    Presentation date: 2008

  • ASAIO Fellowship "Surface properties of dialysis membranes and their effects on biocompatibility"

    American Society for Artificial Internal Organs (ASAIO) 54th Annual Conference / San Francisco, USA 

    Presentation date: 2008

  • Surface properties of dialysis membranes and their effects on biocompatibility

    American Society for Artificial Internal Organs (ASAIO) 54th Annual Conference / San Francisco, USA 

    Presentation date: 2008

  • Characterization of wet dialysis membrane surface by atmic force microscopy

    ICOM 2008 (The 2008 International Congress on Membranes and Membrane Processes) / Hawaii, USA 

    Presentation date: 2008

  • Effects of taper structure of dialyzer jacket on dialysis fluid flow

    XXXV ESAO Congress / geneva, Switerland 

    Presentation date: 2008

  • Characterization of hemodialysis membrane Surface by atmic force microscopy

    The 14th Symposium of Young Asian Biochemical Engineers' Community / Shibaura Institute of Technology 

    Presentation date: 2008

  • Characterization of hemodialysis membrane surface by atomic force microscopy

    The 14th Symposium of Young Asian Biochemical Engineers' Community / Shibaura Institute of Technology 

    Presentation date: 2008

  • Change in proliferation ability and gene expression in lymphocytes in contact with cellulose and polysulfone dialyzer

    XLIV ERA-EDTA Congress / Barcelona, Spain 

    Presentation date: 2007

  • Temperature-controlled intracellular localization of thermoresponsive polymeric micelles

    The 34th Annual Meeting & Exposition of the Controlled Release Society / The long Beach Convention Center, Long Beach, California, USA 

    Presentation date: 2007

  • 生分解性マクロRAFT剤を用いた温度応答性高分子鎖を有するブロックコポリマーの合成とキャラクタリゼーション

    第56回高分子討論会 / 名古屋工業大学 

    Presentation date: 2007

  • 温度応答性酸素濃縮器の開発

    日本人工臓器学会大会(第45回)、第2回国際人工臓器学術大会 / 大阪国際会議場 

    Presentation date: 2007

  • 人工鰓システム用ガスキャリア液の酸素親和力制御

    日本人工臓器学会大会(第45回)、第2回国際人工臓器学術大会 / 大阪国際会議場 

    Presentation date: 2007

  • ドライタイプポリスルホン透析膜の内表面特性

    日本人工臓器学会大会(第45回)、第2回国際人工臓器学術大会 / 大阪国際会議場 

    Presentation date: 2007

  • 透析膜内表面PVPの溶出性

    日本人工臓器学会大会(第45回)、第2回国際人工臓器学術大会 / 大阪国際会議場 

    Presentation date: 2007

  • Evaluation of antioxidant property of vitamin E-coated hollow-fiber dialysis membrane

    The 45th Annual Meeting of the Japanese Society for Artificial Organs, The 2nd Meeting of the International Federation for Artificial Organs / Osaka International Convention Center (OICC) 

    Presentation date: 2007

  • 細胞内デリバリーを実現する温度応答性高分子ミセルシステムの構築

    第29回日本バイオマテリアル学会大会 / 千里ライフサイエンスセンター 

    Presentation date: 2007

  • Preparation and characterization of thermoresponsive block copolymers using biodegradable macro-RAFT agents

    The 10th Pacific Polymer Conference / Kobe International Conference Center 

    Presentation date: 2007

  • Change in proliferation ability and gene expression in lymphocytes in contact with cellulose and polysulfone dialyzer

    XLIV ERA-EDTA Congress / Barcelona, Spain 

    Presentation date: 2007

  • Temperature-controlled intracellular localization of thermoresponsive polymeric micelles

    The 34th Annual Meeting & Exposition of the Controlled Release Society / The long Beach Convention Center, Long Beach, California, USA 

    Presentation date: 2007

  • Evaluation of antioxidant property of vitamin E-coated hollow-fiber dialysis membrane

    The 45th Annual Meeting of the Japanese Society for Artificial Organs, The 2nd Meeting of the International Federation for Artificial Organs / Osaka International Convention Center (OICC) 

    Presentation date: 2007

  • Preparation and characterization of thermoresponsive block copolymers using biodegradable macro-RAFT agents

    The 10th Pacific Polymer Conference / Kobe International Conference Center 

    Presentation date: 2007

▼display all

Research Projects

  • 人工鰓の開発

  • シミュレーション解析によるモジュールの至適設計

  • 分子インプリント膜による選択的透過

  • 電子顕微鏡による透析膜の観察

  • 透析膜の拡散透過係数の測定法

  • 透析膜の構造と透過性

  • スーパーオキシドのモニタリング

  • 人工鰓

  • 生体関連物質の測定法の開発

  • 血液透析膜の構造と透過性

  • Artificial Gill

  • Development of Biosensors for Vital Substances

  • Structure and Permeability of Dialysis Membrane

▼display all

Misc

  • Investigation of molecular surfaces with time-of-flight secondary ion mass spectrometry

    Satoka Aoyagi, Koki Namekawa, Kenichiro Yamamoto, Kiyotaka Sakai, Nobuhiko Kato, Masahiro Kudo

    SURFACE AND INTERFACE ANALYSIS   42 ( 10-11 ) 1593 - 1597  2010.10

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    TOF-SIMS is a promising technique for evaluating biodevices due to its ultrahigh surface sensitivity. Since a cluster ion source such as C(60)(+) provides low collision energy per atom, time-of-flight secondary ion mass spectrometry (TOF-SIMS) with the cluster ion is useful for detecting the uppermost surface of molecules immobilized on a substrate, and therefore, enables the evaluation of the orientation of these immobilized biomolecules. Effects of TOF-SIMS with C(60)(+) were investigated in this study. A relatively small protein, lysozyme, and polypeptides having five amino acid residues, Leu-enkephalin and Met-enkephalin, were employed as model samples. The protein and the polypeptides were immobilized on aminosilanized-indium-tin oxide (ITO) coated glass plates at their N-terminal residues by covalent bonding. The aminosilanized-ITO plate without protein or polypeptide was also prepared as a control sample. After freeze-drying, the samples were measured with TOF-SIMS using gallium and C(60)(+) cluster ion sources, and then TOF-SIMS spectra were analyzed to select peaks specific to each biomolecule by a comparison between the samples. As a result, the C(60)(+) primary ion source showed advantages in evaluating biomolecules, because more peaks at a higher mass generated from the biomolecules can be obtained using C(60)(+) than Ga(+) or Au(3)(+) as the primary ion source, although no difference was detected between the two polypeptide samples under the current measurement conditions. Copyright (C) 2010 John Wiley & Sons, Ltd.

    DOI

  • Membrane potential and charge density of hollow-fiber dialysis membranes

    Ken-ichiro Yamamoto, Takehito Ogawa, Masato Matsuda, Akinori Iino, Taiji Yakushiji, Takehiro Miyasaka, Kiyotaka Sakai

    JOURNAL OF MEMBRANE SCIENCE   355 ( 1-2 ) 182 - 185  2010.06

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    Membrane charge affects diffusive permeability for ions. Hence, evaluation of membrane charge density is necessary to clarify diffusive permeability for ions. The objective of the present study is to measure stable and reproducible membrane potentials with hollow-fiber membranes and to evaluate the electrostatic characteristics of dialysis membrane by applying membrane potential measurement method for flat membrane to hollow-fiber membranes. Membrane charge density was calculated from data on the membrane potential. Values for membrane charge density obtained as electrostatic characteristics of AM-UP150 (regenerated cellulose), KF-15C (ethylenevinylalcohol copolymer), PAN-150SF (polyacrylonitrile), AM-BC150X (polyethylene glycol-modified regenerated cellulose), FB-150U (cellulose triacetate), APS-150E (polysulfone), FLX-15GW (polyester-polymer alloy) and BLF-10GW (diethylaminoethyl-modified regenerated cellulose) were -0.9, -0.9, -0.7, -0.5, -0.1, +0.1, +0.35 and +3.1 mol/m(3), respectively. This method allows determination of the membrane charge density of hollow-fiber dialysis membrane. (C) 2010 Elsevier B.V. All rights reserved.

    DOI CiNii

  • Functional-group analysis of polyvinylpyrrolidone on the inner surface of hollow-fiber dialysis membranes, by near-field infrared microspectroscopy

    Sumire Koga, Taiji Yakushiji, Masato Matsuda, Ken-ichiro Yamamoto, Kiyotaka Sakai

    JOURNAL OF MEMBRANE SCIENCE   355 ( 1-2 ) 208 - 213  2010.06

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    Near-field infrared microspectroscopy (NFIR) is a newly developed surface analysis method that is based on functional-group analysis and has a high spatial resolution. The objective of the present study is to perform nanoscale functional-group analysis of dialysis membrane surfaces by using NFIR. We focused on polyvinylpyrrolidone (PVP), which is employed as an additive to hydrophilize and create pores in synthetic polymer dialysis membranes, and evaluated the PVP distribution on the inner surface of the dialysis membranes. Dialysis membranes made from polysulfone (PSf) and polyester polymer alloy (PEPA) were first assessed by NFIR and then by attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR). The nanoscale NFIR analysis showed heterogeneous distribution of PVP on the PSf membrane even though the amount of PVP on the membrane surface was high. PVP was homogeneously distributed on the PEPA membrane even though the amount of PVP on the membrane surface was low. In contrast, the microscale ATR-FTIR results showed that PVP was homogeneously distributed on both PSf and PEPA membranes. PVP-rich and PVP-poor regions were distinguishable by NFIR and not by ATR-FTIR, because the spatial resolution of NFIR is higher than that of ATR-FTIR. This study demonstrates for the first time that NFIR can provide nanoscale chemical information on the structures of porous membranes. (C) 2010 Elsevier B.V. All rights reserved.

    DOI CiNii

  • Development of a device for chemiluminescence determination of superoxide generated inside a dialysis hollow-fiber membrane

    Takehito Ogawa, Sumire Koga, Taiji Yakushiji, Masato Matsuda, Ken-ichiro Yamamoto, Hiroki Sakata, Makoto Fukuda, Takehiro Miyasaka, Kiyotaka Sakai

    JOURNAL OF ARTIFICIAL ORGANS   13 ( 1 ) 58 - 62  2010.04

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    Reactive oxygen species (ROS) generated during hemodialysis treatment cause dialysis complications because of the high reactivity of ROS. To prevent dialysis complications caused by oxidative stress, it is important to evaluate the generation and dismutation of ROS during hemodialysis treatment. In this study, our aim was to develop a device to determine superoxide (O(2) (-)) generated inside a dialysis hollow fiber, and also to examine whether this device could detect O(2) (-) separated from plasma using hollow fibers. Experimental apparatus was set up so that hypoxanthine (HX) solution flowed inside the hollow fibers and 2-methyl-6-p-methoxyphenylethynyl-imidazopyrazinone (MPEC) solution flowed outside the hollow fibers. Then, xanthine oxidase (XOD) solution was added to the HX solution to generate O(2) (-), and chemiluminescence resulting from the reaction of O(2) (-) with MPEC was measured with an optical fiber. Chemiluminescence intensity was measured at different HX concentrations, and the peak area of relative luminescence intensity yielded a first-order correlation with the HX concentration. Based on the relationship between HX and O(2) (-) concentrations determined by the cytochrome c reduction method, the relative luminescence intensity measured by this device was linearly dependent on the O(2) (-) concentration inside the hollow fibers. After modifications were made to the device, XOD solution injection into plasma including HX resulted in an increase in the relative luminescence intensity. We concluded that this novel device based on chemiluminescence is capable of determining aqueous O(2) (-) generated inside a hollow fiber and also of detecting O(2) (-) in plasma.

    DOI PubMed CiNii

  • � 透析効果率に及ぼす各種影響因子 (1)ダイアライザの形状(設計と仕様)

    山本健一郎, 酒井清孝

    臨床透析 / 日本メディカルセンター   26 ( 4 ) 413 - 418  2010

  • 論文賞受賞レポート "Effects of fluid flow on elution of hydrophilic modifier from dialysis membrane surface"

    松田雅人, 佐藤美佳, 阪田宏樹, 小川貴久, 山本健一郎, 薬師寺大二, 福田誠, 宮坂武寛, 酒井清孝

    人工臓器 / 学研メディカル秀潤社   39 ( 1 ) 31 - 32  2010

  • Development of an enzyme-free glucose sensor using the gate effect of a molecularly imprinted polymer

    Yasuo Yoshimi, Akisato Narimatsu, Keisuke Nakayama, Shinichi Sekine, Koji Hattori, Kiyotaka Sakai

    JOURNAL OF ARTIFICIAL ORGANS   12 ( 4 ) 264 - 270  2009.12

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    The instability of enzymatic glucose sensors has prevented the development of a practical artificial pancreas for diabetic patients. We therefore developed an enzyme-free glucose sensor using the gate effect of a molecularly imprinted polymer (MIP). This sensor has the advantages of improved stability and a simplified manufacturing procedure. An adduct of glucose and 4-vinylphenylboronic acid (VPBA) was synthesized by esterification and was then purified. The copolymer of the glucose/VPBA adduct and methylene bisacrylamide was grafted onto an indium tin oxide electrode surface. Glucose was washed out from the copolymer to obtain an MIP layer. Cyclic voltammetry of ferrocyanide in aqueous solution was performed using an MIP-grafted electrode, and the effect of glucose on the anodic current intensity was evaluated. The anodic current intensity was sensitive to the glucose concentration, and the dynamic range (0-900 mg/dl) covered the typical range of diabetic blood glucose levels. The response time of the MIP-grafted electrode to a stepwise change in the glucose concentration was approximately 3-5 min. Thus, we can conclude that, by taking advantage of its gate effect, it is feasible to use an MIP-grafted electrode as a glucose sensor for monitoring blood sugar in diabetic patients.

    DOI CiNii

  • Fluorescence Enhancement of Fluorescein Isothiocyanate-Labeled Protein A Caused by Affinity Binding with Immunoglobulin G in Bovine Plasma

    Takehito Ogawa, Satoka Aoyagi, Takehiro Miyasaka, Kiyotaka Sakai

    SENSORS   9 ( 10 ) 8271 - 8277  2009.10

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    Fluorescence enhancement of fluorescein isothiocyanate-labeled protein A (FITC-protein A) caused by the binding with immunoglobulin G (IgG) in bovine plasma was studied. FITC-protein A was immobilized onto a glass surface by covalent bonds. An increase in fluorescence intensity was dependent on IgG concentration ranging from 20 to 78 mu g/mL in both phosphate buffer saline and bovine plasma. This method requires no separation procedure, and the reaction time is less than 15 min. A fluorescence enhancement assay by the affinity binding of fluorescence-labeled reagent is thus available for the rapid determination of biomolecules in plasma.

    DOI

  • Temperature-Induced Intracellular Uptake of Thermoresponsive Polymeric Micelles

    Jun Akimoto, Masamichi Nakayama, Kiyotaka Sakai, Teruo Okano

    BIOMACROMOLECULES   10 ( 6 ) 1331 - 1336  2009.06

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    Well-defined diblock copolymers comprising thermoresponsive segments of poly(N-isopropylacrylamide-co-N,N-dimethylacrylamide) (P(IPAAm-co-DMAAm)) and hydrophobic segments of poly(D,L-lactide) were synthesized by combination of RAFT and ring-opening polymerization methods. Terminal conversion of thermoresponsive segments was achieved through reactions of maleimide or its Oregon Green 488 (OG) derivative with thiol groups exposed by cleavage of polymer terminal dithiobenzoate groups. Thermoresponsive micelles obtained from these polymers were approximately 25 nm when below the lower critical solution temperature (LCST) of 40 degrees C, and their sizes increased to an average of approximately 600 nm above the LCST due to aggregation of the micelles. Interestingly, the OG-labeled thermoresponsive micelles showed thermally regulated internalization to cultured endothelial cells, unlike linear thermoresponsive P(IPAAm-co-DMAAm) chains. While intracellular uptake of P(IPAAm-co-DMAAm) was extremely low at temperatures both below and above the micellar LCST, the thermoresponsive micelles showed time-dependent intracellular uptake above the LCST without exhibiting cytotoxicity. These results indicate that the new thermoresponsive micelle system may be a greatly promising intracellular drug delivery tool.

    DOI PubMed CiNii

  • Computational Evaluation of Dialysis Fluid Flow in Dialyzers With Variously Designed Jackets

    Ken-ichiro Yamamoto, Masato Matsuda, Ayaka Hirano, Natsuo Takizawa, Shigeto Iwashima, Taiji Yakushiji, Makoto Fukuda, Takehiro Miyasaka, Kiyotaka Sakai

    ARTIFICIAL ORGANS   33 ( 6 ) 481 - 486  2009.06

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    Dialyzer performance strongly depends on the flow of blood and dialysis fluid as well as membrane performance. It is necessary, particularly to optimize dialysis fluid flow, to develop a highly efficient dialyzer. The objective of the present study is to evaluate by computational analysis the effects of dialyzer jacket baffle structure, taper angle, and taper length on dialysis fluid flow. We modeled 10 dialyzers of varying baffle angles (0, 30, 120, 240, and 360 degrees) with and without tapers. We also modeled 30 dialyzers of varying taper lengths (0, 12.5, 25.0, and 50.0 mm) and angles (0, 2, 4, and 6 degrees) based on technical data of APS-SA dialyzers having varying surface areas of 0.8, 1.5, and 2.5 m(2) (Rexeed). Dialysis fluid flow velocity was calculated by the finite element method. The taper part was divided into 10 sections of varying fluid resistances. A pressure of 0 Pa was set at the dialysis fluid outlet, and a dialysis fluid flow rate of 500 mL/min at the dialysis fluid inlet. Water was used as the dialysis fluid in the computational analysis. Results for dialysis fluid flow velocity of the modeled dialyzers indicate that taper design and a fully surrounded baffle are important in making the dialysis fluid flow into a hollow-fiber bundle easily and uniformly. However, dialysis fluid flow channeling occurred particularly at the outflowing part with dialyzers having larger taper lengths and angles. Optimum design of dialysis jacket structure is essential to optimizing dialysis fluid flow and to increasing dialyzer performance.

    DOI

  • Flow Uniformity in Oxygenators with Different Outlet Port Design

    Ayaka Hirano, Ken-Ichiro Yamamoto, Masato Matsuda, Masaru Inoue, Sukemasa Nagao, Katsuyuki Kuwana, Masahiro Kamiya, Kiyotaka Sakai

    ASAIO JOURNAL   55 ( 3 ) 209 - 212  2009.05

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    This study reports on evaluation of the optimum design of a blood outlet port structure for providing uniform flow by visualizing the blood flow in an extracapillary membrane oxygenator. We tested a cylindrical type extracapillary membrane oxygenator, HPO-20. The HPO-20 has a tangential blood outlet port and is thus referred to as "Tangential HPO20." We engineered "Vertical HPO-20" with a vertical blood outlet port by modifying the Tangential HPO-20. To visualize the blood-side flow, a total of 120 insulated copper-wire electrodes were placed in the "Tangential" and the Vertical HPO-20s. The test solution flow was visualized by the dimensionless fluid arrival time reaching each electrode. The test solution flow in the Tangential HPO-20 was not uniform, particularly at the outside blood channel. The flow was more uniform in the Vertical HPO-20. The blood flow in an extracapillary membrane oxygenator with a vertical blood outlet port is well distributed so that it produces more uniform blood flow than that with a tangential outlet port because of the small stagnation and reduced channeling. ASAIO Joumal 2009; 55:209-212.

    DOI PubMed CiNii

  • Technical Characterization of Dialysis Fluid Flow of Newly Developed Dialyzers Using Mass Transfer Correlation Equations

    Satoru Kunikata, Makoto Fukuda, Ken-Ichiro Yamamoto, Yutaka Yagi, Masato Matsuda, Kiyotaka Sakai

    ASAIO JOURNAL   55 ( 3 ) 231 - 235  2009.05

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    Dialysis fluid flow and mass transfer rate of newly developed dialyzers were evaluated using mass transfer correlation equations of dialysis fluid-side film coefficient. Aqueous creatinine clearance and overall mass transfer coefficient for APS-15S (Asahi Kasei Kuraray) as a conventional dialyzer, and APS-15SA (Asahi Kasei Kuraray), PES-150S alpha (Nipro), FPX140 (Fresenius), and CS-1.61U (Toray) as newly developed dialyzers were obtained at a blood-side flow rate (Q,) of 200 ml/min, dialysis fluid-side flow rates (Q(D)) of 200-800 ml/min and a net filtration rate (Q,) of 0 ml/min. Mass transfer correlation equations between Sherwood number (Sh) containing dialysis fluid-side mass transfer film coefficient and Reynolds number (Re) were formed for each dialyzer. The exponents of Re were 0.62 for APS-15S whereas approximately 0.5 for the newly developed dialyzers. The dialysis fluid-side mass transfer film coefficients of the newly developed dialyzers were higher than those of the conventional dialyzer. Based on the mass transfer correlation equations, introduction of short taper, full baffle of dialyzer jacket and further wave-shaped hollow fiber improves the dialysis fluid flow of the newly developed dialyzers. ASAIO journal 2009; 55:231-235.

    DOI PubMed CiNii

  • Nanotechnological Characterization of Human Serum Albumin Adsorption on Wet Synthetic Polymer Dialysis Membrane Surfaces

    Koki Namekawa, Makoto Fukuda, Masato Matsuda, Yutaka Yagi, Ken-Ichiro Yamamoto, Kiyotaka Sakai

    ASAIO JOURNAL   55 ( 3 ) 236 - 242  2009.05

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    The objective of the present study was to evaluate the characteristics of protein adsorption on the inner surface of various dialysis membranes, to develop protein adsorption-resistant biocompatible dialysis membranes. The adsorption force of human serum albumin (HSA) on the inner surface of a dialysis membrane and the smoothness of the membrane were evaluated from a nanoscale perspective by atomic force microscopy. The content ratio of the hydrophilic polymer, polyvinylpyrrolidone (PVP), was determined by attenuated total reflection Fourier transform infrared spectroscopy. Nine synthetic-polymer dialysis membranes on the market made of polysulfone (PSF), polyethersulfone (PES), polyester polymer-alloy (PEPA), and ethylene vinylalcohol (EVAL) were used in the present study. The HSA adsorption force on the surface of the hydrophobic polymer PEPA membrane was higher than that on the hydrophilic polymer EVAL membrane surface. It has been considered beneficial, for decreasing the HSA adsorption force, to cover a hydrophobic polymer membrane surface with PVP. However, there were some areas on PVP-containing membrane surfaces at which much higher HSA adsorption forces were observed. The HSA adsorption force gave a nearly linear correlation with the surface roughness on the PSF membrane surface. However, the HSA adsorption force was uncorrelated with the PVP content ratio for any of the PSF membrane surfaces tested. in conclusion, protein adsorption can be minimized by the use of dialysis membranes made of hydrophobic polymers containing PVP with a smooth surface. ASAIO journal 2009; 55:236-242.

    DOI PubMed CiNii

  • 血液透析濾過(HDF)透析器の設計に関する基礎的検討

    松石健太郎, 八木優, 松田雅人, 山本健一郎, 福田誠, 酒井清孝

    腎と透析 別冊ハイパフォーマンスメンブレン'09 / 東京医学社   67   149 - 152  2009

  • 透析膜における溶質透過挙動の可視化

    佐伯努, 松田雅人, 山本健一郎, 薬師寺大二, 酒井清孝

    腎と透析 別冊ハイパフォーマンスメンブレン'09 / 東京医学社   67   135 - 137  2009

  • EVAL透析膜とPVP配合合成高分子膜のHSA吸着力の比較

    滑川亘希, 八木優, 松田雅人, 山本健一郎, 福田誠, 酒井清孝

    腎と透析 別冊ハイパフォーマンスメンブレン'09 / 東京医学社   67   127 - 131  2009

  • PVP配合率の異なるPEPA膜からのPVP溶出特性

    青松香里, 滑川亘希, 八木優, 松田雅人, 山本健一郎, 福田誠, 酒井清孝

    腎と透析 別冊ハイパフォーマンスメンブレン'09 / 東京医学社   67   121 - 126  2009

  • 近接場顕微赤外分光法による透析膜表面におけるポリビニルピロリドン(PVP)分子の分析

    古賀すみれ, 薬師寺大二, 松田雅人, 山本健一郎, 酒井清孝

    腎と透析 別冊ハイパフォーマンスメンブレン'09 / 東京医学社   67   116 - 120  2009

  • APS-15SAの性能の経時変化に及ぼす血液流量および濾液流量の影響

    櫻原菜緒, 酒井清孝, 石森勇, 吉田智史, 崎山亮一, 峰島三千男

    腎と透析 別冊ハイパフォーマンスメンブレン'09 / 東京医学社   67   46 - 50  2009

  • 化学工学と企業経営の接点を探る ~学生編集委員企画による経営者インタビュー~ 住友化学(株)副社長 神田直哉氏に聞く

    清水俊行, 長谷川馨, 木村理一郎, 滑川亘希

    化学工学 / 化学工学会   73 ( 11 ) 556 - 561  2009

  • Thermoresponsive protein adsorption of poly(N-isopropylacrylamide)-modified streptavidin on polydimethylsiloxane microchannel surfaces

    Shinji Sugiura, Wataru Imano, Toshiyuki Takagi, Kiyotaka Sakai, Toshiyuki Kanamori

    BIOSENSORS & BIOELECTRONICS   24 ( 5 ) 1135 - 1140  2009.01

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    The control of protein adsorption on microchannel Surfaces is important for biosensors. In this Study, we demonstrated protein adsorption method that is controlled through temperature change, i.e., thermoresponsive protein adsorption, on polydimethylsiloxane (PDMS) microchannel surfaces using a thermoresponsive polymer, poly(N-isopropylacrylamide) (PNIPAAm). To provide general protein adsorption control method, we adopted biotin-streptavidin chemistry and synthesized streptavidin covalently modified with PNIPAAm (PNIPAAm-StAv). Modification of streptavidin, a hydrophilic protein, with PNIPAAm induced successful thermoresponsive adsorption on a PDMS microchannel Surfaces: PNIPAAm-StAv adsorbed at 37 degrees C and desorbed at 10 degrees C on the surfaces. We also demonstrated the thermoresponsive adsorption of biotinylated immunoglobulin G (IgG-b) using PNIPAAm-StAv. Conjugation of IgG-b with PNIPAAm-StAv induced successful thermoresponsive IgG-b adsorption on PDMS. Modification of PDMS surfaces with PNIPAAm reduced physical adsorption of the partially hydrophobic IgG-b on the surface and contributed to the high-contrast thermoresponsive adsorption of IgG-b: less than 1% of the IgG-b adsorbed at 37,C was detected after the PNIPAAm-PDMS surface was washed at 10 degrees C. The controllable adsorption of this system is expected to be applied to the regeneration of biosensor chips and to on-chip protein manipulation. (c) 2008 Elsevier B.V. All rights reserved.

    DOI

  • Molecular Design of Outermost Surface Functionalized Thermoresponsive Polymeric Micelles with Biodegradable Cores

    Jun Akimoto, Masamichi Nakayama, Kiyotaka Sakai, Teruo Okano

    JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY   46 ( 21 ) 7127 - 7137  2008.11

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    We prepared well-defined diblock copolymers of thermoresponsive poly(N-isopropylacrylamide-co-N,N-dimethylacrylamide) blocks and biodegradable poly(D,L-lactide) blocks by combination of reversible addition-fragmentation chain transfer radical (RAFT) polymerization and ring-opening polymerization. alpha-Hydroxyl, omega-dithiobenzoate thermoresponsive polymers were synthesized by RAFT polymerization using hydroxyl RAFT agents. Biodegradable blocks were prepared by ring-opening polymerization Of D,L-lactide initiated by a-hydroxyl groups of thermoresponsive polymers, which inhibit the thermal decomposition of omega-dithioester groups. Terminal dithiobenzoate (DTBz) groups of thermoresponsive blocks were easily reduced to thiol groups and reacted with maleimide (Mal). In aqueous media, diblock copolymer products formed surface-functionalized thermoresponsive micelles. These polymeric micelles had a low critical micelle concentration of 22 mu g/L. In thermoresponsive studies of the micelles, hydrophobic DTBz-surface micelles demonstrated a significant shift in lower critical solution temperature (LCST) to a lower temperature of 30.7 degrees C than that for Mal-surface micelles (40.0 degrees C). In addition, micellar LCST was controlled by changing bulk mixture ratios of respective heterogeneous end-functional diblock copolymers. Micellar disruption at acidic condition (pH 5.0) was completed within 5 days due to hydrolytic degradation of PLA cores, regardless of showing a slow disruption rate at physiological condition. Furthermore, we successfully improved water-solubility of hydrophobic drug, paclitaxel by incorporating into the micellar cores. (C) 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7127-7137, 2008

    DOI CiNii

  • Effects of fluid flow on elution of hydrophilic modifier from dialysis membrane surfaces

    Masato Matsuda, Mika Sato, Hiroki Sakata, Takahisa Ogawa, Ken-ichiro Yamamoto, Taiji Yakushiji, Makoto Fukuda, Takehiro Miyasaka, Kiyotaka Sakai

    JOURNAL OF ARTIFICIAL ORGANS   11 ( 3 ) 148 - 155  2008.09

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    When uremic blood flows through dialyzers during hemodialysis, dialysis membrane surfaces are exposed to shear stress and internal filtration, which may affect the surface characteristics of the dialysis membranes. In the present study, we evaluated changes in the characteristics of membrane surfaces caused by shear stress and internal filtration using blood substitutes: water purified by reverse osmosis and 6.7 wt% dextran70 solution. We focused on the levels of a hydrophilic modifier, polyvinylpyrrolidone (PVP), on the membrane surface measured by attenuated total reflectance Fourier transform infrared spectroscopy. Experiments involving 4 h dialysis, 0-144 h shear-stress loading, and 4 h dead-end filtration were performed using polyester-polymer alloy (PEPA) and polysulfone (PS) membranes. After the dialysis experiments with accompanying internal filtration, average PVP retention on the PEPA membrane surface was 93.7% in all areas, whereas that on the PS membrane surface was 98.9% in all areas. After the shear-stress loading experiments, PVP retention on the PEPA membrane surface decreased as shear-stress loading time and the magnitude of shear stress increased. However, with the PS membrane, PVP retention scarcely changed. After the dead-end filtration experiments, PVP retention decreased in all areas for both PEPA and PS membranes, but PVP retention on the PEPA membrane surface was lower than that on the PS membrane surface. PVP on the PEPA membrane surface was eluted by both shear stress and internal filtration, while that on the PS membrane surface was eluted only by internal filtration.

    DOI PubMed CiNii

  • The effect of extensible PEG tethers on shielding between grafted thermo-responsive polymer chains and integrin-RGD binding

    Mitsuhiro Ebara, Masayuki Yamato, Takao Aoyagi, Akihiko Kikuchi, Kiyotaka Sakai, Teruo Okano

    BIOMATERIALS   29 ( 27 ) 3650 - 3655  2008.09

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    The affinity control of integrin-RGD (Arg-Gly-Asp) binding by a thermal "on-off' switch has been achieved using newly designed surfaces presenting grafted temperature-responsive poly(N-isopropylacrylamide-co-2-carboxyisopropylacrylamide) copolymers functionalized with synthetic peptides. The prepared surface was designed to expose the tethered peptides available for cell binding at active "on" state above the lower critical solution temperature (LCST). The fully extended chains, on the other hand, masked the peptides completely and the cells started to detach from the surfaces at inactive "off' sate below the LCST. This paper elucidates the shielding effect of the grafted polymer chains on the dissociation of integrin-RGD binding below the LCST. To assess the ability of the polymer-shielding, extensible poly(ethylene glycol) (PEG) tethers were introduced between peptides and the grafted polymers. PEG chains allow peptides to be tethered to surfaces via functional PEG end-groups, leading to active "on" state even below the LCST. The time required to release cells from the surface was found to be longer when peptides were coupled to an extensible tether ends, suggesting that the surfaces can engender cell attachment through adhesive moieties covalently bound to the free ends of PEG chains. These results indicate that architectural changes on the nanometer length scale are crucial for controlling integrin-RGD binding and one of the main factors causing cell detachment is the shielding effect of the grafted polymer chains. (C) 2008 Elsevier Ltd. All rights reserved.

    DOI PubMed CiNii

  • A novel approach to observing synergy effects of PHSRN on integrin-RGD binding using intelligent surfaces

    Mitsuhiro Ebara, Masayuki Yamato, Takao Aoyagi, Akihiko Kikuchi, Kiyotaka Sakai, Teruo Okano

    ADVANCED MATERIALS   20 ( 16 ) 3034 - 3038  2008.08

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    A novel assay for measuring time-dependant ligand-receptor affinity changes is developed based on a peptide-immobilized temperature-responsive surface, as schematically illustrated in the figure. The grafted thermoresponsive polymer acts as an "on-off" switch for mediating integrin-peptide bonding. At temperatures above and below the lower critical solution temperature (LCST), the peptides are accessible and shielded from integrin access, respectively.

    DOI CiNii

  • Nanotechnological evaluation of protein adsorption on dialysis membrane surface hydrophilized with polyvinylpyrrolidone

    Masato Matsuda, Ken-ichiro Yamamoto, Taiji Yakushiji, Makoto Fukuda, Takehiro Miyasaka, Kiyotaka Sakai

    JOURNAL OF MEMBRANE SCIENCE   310 ( 1-2 ) 219 - 228  2008.03

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    Hydrophilizing synthetic polymer dialysis membranes with polyvinylpyrrolidone (PVP) play an important role for inhibition of protein adsorption on membrane surface. In the present study, the effect of PVP on protein adsorption was evaluated from a nano-scale perspective. Swelling behavior of PVP present on wet polysulfone (PS)/PVP film surfaces was observed by atomic force microscopy (AFM). Fibrinogen and human serum albumin (HSA) were immobilized on the tip of AFM probes, with which a force-curve between protein and wet PS/PVP film surface was measured by AFM while scanning in order to visualize two-dimensional protein adsorbability on film surfaces. Furthermore, HSA adsorbability on non-PVP containing PEPA dialysis membrane (FLX-15GW) and PVP containing PEPA dialysis membrane (FDX-150GW) was evaluated by the AFM force-curve method. As a result, PS/PVP film surface was completely covered with hydrated and swollen PVP at 5 wt% or more PVP content. Protein adsorbability on PS/PVP film surfaces decreased greatly with increasing content of PVP. The adsorption of HSA was inhibited by the presence of PVP on film surfaces more significantly than that of more hydrophobic fibrinogen. HSA adsorbability on wet FLX-15GW dialysis membrane surface was 428+/-174 pN whereas that on wet FDX-150GW dialysis membrane surface was 42+/-29 pN. (C) 2007 Elsevier B.V. All rights reserved.

    DOI CiNii

  • 理工の知が築いた後世への遺産

    編集委員会

    早稲田大学理工学部百年誌 / 早稲田大学     170  2008

  • 原子間力顕微鏡による血液透析膜の生体適合性の評価

    八木優, 松田雅人, 滑川亘希, 國方賢, 山本健一郎, 酒井清孝, 福田誠, 薬師寺大二, 宮坂武寛

    腎と透析 別冊ハイパフォーマンスメンブレン'08 / 東京医学社   65   64 - 67  2008

  • 透析膜へのずり応力負荷が親水化剤溶出および表面構造に与える影響

    朝妻恵一, 松田雅人, 山本健一郎, 薬師寺大二, 福田誠, 宮坂武寛, 酒井清孝

    腎と透析 別冊ハイパフォーマンスメンブレン'08 / 東京医学社   65   60 - 63  2008

  • 最新の合成高分子系血液透析膜の内表面特性評価

    滑川亘希, 八木優, 松田雅人, 山本健一郎, 福田誠, 薬師寺大二, 宮坂武寛, 酒井清孝

    腎と透析 別冊ハイパフォーマンスメンブレン'08 / 東京医学社   65   51 - 55  2008

  • 新型血液透析器における透析液側流動の無次元相関式による評価

    國方賢, 八木優, 松田雅人, 山本健一郎, 福田誠, 薬師寺大二, 宮坂武寛, 酒井清孝

    腎と透析 別冊ハイパフォーマンスメンブレン'08 / 東京医学社   65   47 - 50  2008

  • コンピュータシミュレーションによる透析器のハウジング形状が透析液流動に及ぼす影響の解析

    滝沢夏生, 山本健一郎, 松田雅人, 薬師寺大二, 福田誠, 宮坂武寛, 酒井清孝

    腎と透析 別冊ハイパフォーマンスメンブレン'08 / 東京医学社   65   42 - 46  2008

  • 透析膜表面PVP減少が表面特性に与える影響

    松田雅人, 朝妻恵一, 阪田宏樹, 山本健一郎, 薬師寺大二, 福田誠, 宮坂武寛, 酒井清孝

    腎と透析 別冊ハイパフォーマンスメンブレン'08 / 東京医学社   65   56 - 59  2008

  • 膜構造制御によるアルブミン漏出の抑制

    松田雅人, 久保宜昭, 山本健一郎, 薬師寺大二, 福田誠, 宮坂武寛, 酒井清孝

    腎と透析 別冊ハイパフォーマンスメンブレン'08 / 東京医学社   65   26 - 29  2008

  • 湿潤透析膜表面特性のナノレベル評価の必要性

    松田雅人, 朝妻恵一, 阪田宏樹, 山本健一郎, 薬師寺大二, 福田誠, 宮坂武寛, 酒井清孝

    医工学治療 / 特定非営利活動法人日本医工学治療学会   20 ( 4 ) 246 - 250  2008

  • 透析器の軸方向および断面方向における親水化剤溶出性

    佐藤 美佳, 松田 雅人, 薬師寺 大二, 福田 誠, 宮坂 武寛, 山本 健一郎, 酒井 清孝

    医工学治療   19 ( 4 ) 251 - 255  2007.12

     View Summary

    透析で用いられている合成高分子膜のうち、ポリスルホン(PS)とポリエステル系ポリマアロイ(PEPA)は、親水化剤であるポリビニルピロリドン(PVP)を添加することによって膜表面を親水化し、生体適合性の向上を図っている。しかし、透析により生じる中空糸膜表面のPVP分布の変化を定量的に検討した例はない。そこで、本研究では、透析器内の中空糸膜を軸方向および断面方向のいくつかのエリアに分け、各エリアにおける膜表面PVP残存率を測定し、PVPの溶出性を評価した。APS-15EX(試作品:PS膜、旭化成メディカル)およびFDX-15GW(PEPA膜、日機装)の透析器を用いて、血液側流量200mL/min、透析液側流量500mL/minで4時間透析を行った。このとき、血液側には血液と同粘度を有する6.7wt%デキストラン70水溶液、透析液側には逆浸透水を用いた。透析終了後に透析器ジャケットを取り外し、各エリア(透析器軸方向に3分割、断面方向に12分割、合計36エリア)から中空糸を取り出した。全反射減衰フーリエ変換赤外分光法(FTIR/ATR)で透析前後の中空糸膜内表面におけるPVP残存率を測定した。APS-15EXおよびFDX-15GWのいずれの透析器も、透析によって膜表面PVP残存率はすべてのエリアで減少しており、すべてのエリアでPVPが溶出したことがわかった。なお、APS-15EXとFDX-15GWの平均PVP残存率は、それぞれ94.1%、90.8%となり、APS-15EXの方が若干高いPVP残存率を示した。さらに、断面方向と軸方向で比較したところ、いずれの透析器も次のように同様の傾向を示した。断面方向では各断面にPVP残存率の偏りがみられた。軸方向では、中空糸束中央部に比較して、内部濾過量の多い中空糸束両端部においてPVP残存率が著しく低下した。特に、濾過が生じている血液出口部において、この傾向は顕著であった。(著者抄録)

  • Influence of solvents on chiral discriminative gate effect of molecularly imprinted poly(ethylene glycol dimethacrylate-co-methacrylic acid)

    Shinichi Sekine, Yuta Watanabe, Yasuo Yoshimi, Koji Hattori, Kiyotaka Sakai

    SENSORS AND ACTUATORS B-CHEMICAL   127 ( 2 ) 512 - 517  2007.11

     View Summary

    This paper discusses the chiral discriminative gate effect of molecularly imprinted polymer (MIP) in organic solvents. We grafted L- (or D-) phenylalanine anilide (PAA) imprinted poly(ethylene glycol dimethacrylate-co-methacrylic acid) on an indium-tin oxide (ITO) in a number of organic solvents. Cyclic voltammetry of ferrocene with the grafted ITO electrode was carried out in several organic solvents and the effect Of L-(or D-) PAA on an electric current of ferrocene was evaluated. As the result, the faradic current at the electrode grafted in the non-polar solvent was remarkably sensitive to the template in the voltammetry carried out in the non-polar solvent. However, it was insensitive to the enantiomer of the template. The results indicate that the gate effect of MIP can discriminate between the template and its analogue by stereochemical structure even if the difference in the chemical or physical property is omitted. They also indicate that the gate effect could have limited applications with the enantio-selective amperometric sensors working in non-polar solvents where biosensors cannot work. (c) 2007 Elsevier B.V. All rights reserved.

    DOI CiNii

  • Thermal modulation of intracellular drug distribution using thermoresponsive polymeric micelles

    M. Nakayama, J. E. Chung, T. Miyazaki, M. Yokoyama, K. Sakai, T. Okano

    REACTIVE & FUNCTIONAL POLYMERS   67 ( 11 ) 1398 - 1407  2007.11

     View Summary

    Intracellular distribution of free doxorubicin (DOX) or DOX-loaded in polymeric micelles with thermoresponsive outer shells of poly(N-isopropylacrylamide) or its copolymers in cultured human breast cancer cells (MCF-7) were investigated by fluorescence and confocal laser scanning microscopy. Free DOX accumulated rapidly and selectively in cell nuclei, independent of temperature changes. In contrast to free drugs, the intracellular distribution of DOX-loaded in the thermoresponsive polymeric micelles was significantly affected by temperature changes across lower critical solution temperature (LCST) of the micelles. Above the micelle LCST, DOX delivered by the micelles was localized uniformly inside of MCF-7 cells. By contrast, the amount of DOX delivered to MCF-7 cells drastically decreased below the micelle LCST due to minimal interaction of the micelles with cell membrane surfaces. These results clearly showed that the mechanism of the intracellular drug localization was different between free drugs and DOX-loaded in the micelles. The thermoresponsive micelles aggressively interacted with the cells and carried DOX into the cells via triggered phase transition of the outer shells. In addition, much lower accumulation of free DOX was observed in the resistant cells compared to its parent sensitive MCF-7 due to the resistant mechanism. Of interest, DOX accumulation in the resistant cells was almost in the same level as with MCF-7 (sensitive) cells for the micelle system above the LCST. (c) 2007 Elsevier Ltd. All rights reserved.

    DOI CiNii

  • Antioxidation property of vitamin E-coated polysulfone dialysis membrane an recovery of oxidize vitamin E by vitamin C treatment

    Ken-Ichiro Yamamoto, Masato Matsuda, Masashi Okuoka, Taiji Yakushiji, Makoto Fukudab, Takehiro Miyasaka, Yutaka Matsumoto, Kiyotaka Sakai

    JOURNAL OF MEMBRANE SCIENCE   302 ( 1-2 ) 115 - 118  2007.09

     View Summary

    The antioxidation property of vitamin E-coated dialysis membrane is effective for reduction of oxidative stress. Effect of amount of vitamin E coating on antioxidation property has been poorly understood yet. In the present study, we evaluated a relationship between amount of vitamin E coating and antioxidation property using a superoxide probe of 2-methyl-6-p-methoxyphenylethynylimidazopyrazinone (MPEC) by the optical fiber method to determine optimum amount of vitamin E coating and to improve antioxidation property of the vitamin E-coated dialysis membrane. Furthermore, from the viewpoint of reuse, we examined recovery of oxidized vitamin E by vitamin C treatment. In conclusion, it is necessary to coat polysulfone dialysis membranes with vitamin E at over 74 mg/m(2). The antioxidation property is recoverable by treating dialysis membrane containing oxidized vitamin E with vitamin C. By administrating vitamin C, higher antioxidation property may be realized with a small amount of vitamin E coating. (c) 2007 Elsevier B.V. All rights reserved.

    DOI CiNii

  • 生体機能代行装置(人工臓器)

    酒井清孝

    化学工学 / 化学工学会   71 ( 1 ) 63 - 66  2007

  • 分子インプリント透析膜による濾過流量の制御

    大西孝, 服部浩二, 吉見靖男, 酒井清孝

    腎と透析 別冊ハイパフォーマンスメンブレン'07 / 東京医学社   63   32 - 34  2007

  • 血液中のNOをモニタリングできる新しいシステムの開発

    松川裕章, 奥岡眞視, 松田雅人, 薬師寺大二, 福田誠, 宮坂武寛, 山本健一郎, 酒井清孝

    腎と透析 別冊ハイパフォーマンスメンブレン'07 / 東京医学社   63   38 - 40  2007

  • アルブミン漏出を抑制する非対称膜の設計

    南めぐみ, 松田雅人, 山本健一郎, 薬師寺大二, 福田誠, 宮坂武寛, 酒井清孝

    腎と透析 別冊ハイパフォーマンスメンブレン'07 / 東京医学社   63   41 - 43  2007

  • APS-DRY膜の表面キャラクタリゼーション

    松田雅人, 山本健一郎, 薬師寺大二, 福田誠, 宮坂武寛, 小泉智徳, 吉田一, 酒井清孝

    腎と透析 別冊ハイパフォーマンスメンブレン'07 / 東京医学社   63   44 - 46  2007

  • 新型透析器のパルスレスポンス法と局所圧力測定による透析液流動評価

    長谷川真衣, 山本健一郎, 酒井清孝, 薬師寺大二, 福田誠, 宮坂武寛

    腎と透析 別冊ハイパフォーマンスメンブレン'07 / 東京医学社   63   62 - 65  2007

  • 血液流動ストレスに対するポリスルホン膜内表面の親水化剤耐溶出性

    佐藤美佳, 小川貴久, 松田雅人, 薬師寺大二, 福田誠, 宮坂武寛, 山本健一郎, 酒井清孝

    腎と透析 別冊ハイパフォーマンスメンブレン'07 / 東京医学社   63   66 - 68  2007

  • 論文賞(代謝領域)受賞レポートhollow-fiber blood-dialysis membranes: superoxide generation, permeation, and dismutation measured by chemiluminescence

    山本健一郎, 小林憲由, 遠藤恒介, 宮坂武寛, 望月精一, 小堀深, 酒井清孝

    人工臓器 / 日本人工臓器学会   36 ( 1 ) 86 - 87  2007

    DOI CiNii

  • 人生万事塞翁が馬

    坂本裕馬

    化学工学 / 化学工学会   71 ( 6 ) 402  2007

  • いつのまにか科学者のはしくれに

    青柳里果

    化学工学 / 化学工学会   71 ( 5 ) 328 - 329  2007

  • 重篤な腎不全の治療に使われる透析膜と透析器

    山本健一郎, 酒井清孝

    化学と教育 / 日本化学会   55 ( 7 ) 346 - 347  2007

    DOI CiNii

  • Evaluation of asymmetrical structure dialysis membrane by tortuous capillary pore diffusion model

    Ken-ichiro Yamamoto, Masayo Hayama, Masato Matsuda, Taiji Yakushiji, Makoto Fukuda, Takehiro Miyasaka, Kiyotaka Sakai

    JOURNAL OF MEMBRANE SCIENCE   287 ( 1 ) 88 - 93  2007.01

     View Summary

    The tortuous capillary pore diffusion model (TCPDM) has been used for estimating diffusive and pure water permeability from simple structure parameters such as pore diameter, surface porosity, wall thickness and tortuosity. The validity of this model for evaluation of homogeneous membrane has been already confirmed. Recently, there is a trend toward the use of asymmetrical dialysis membranes made of synthetic polymer such as poly(acrylonitrile) (PAN), polysulfone (PS) and a polyethersulfone polyarylate (PEPA) blend polymer. The purpose of the present study is to apply the TCPDM to evaluation of commercially available hollow-fiber dialysis membranes with asymmetrical structures by simplifying them to a double-layer membrane. The TCPDM is capable of estimating pore tortuosity of asymmetrical dialysis membranes having skin and supporting layers from data on membrane thickness, pore diameter, pure water permeability and water content. Values for diffusive permeability obtained by the TCPDM are in a good agreement with experimental data. This TCPDM model is useful for evaluation of not only homogeneous membrane but also asymmetrical membrane. (c) 2006 Elsevier B.V. All rights reserved.

    DOI CiNii

  • Electrical oscillation at a water/octanol interface in a hydrophobic container

    Takehito Ogawa, Hiroshi Shimazaki, Satoka Aoyagi, Kiyotaka Sakai

    JOURNAL OF COLLOID AND INTERFACE SCIENCE   305 ( 1 ) 195 - 197  2007.01

     View Summary

    The electrical potential oscillation at and the shape of the water/octanol interface were investigated using hydrophobic fluoroplastic containers. The interfacial potential between a water solution containing 1.5 mM sodium dodecyl sulfate (SDS) and an octanol solution containing 5 mM tetrabutylammonium chloride oscillated with an amplitude of 50-100 mV. The potential oscillation was also observed using a transparent fluoroplastic tube. The water/octanol interface shape was unchanged and no interfacial flow was observed during the oscillation. The interface shape was convex toward the octanol phase for 1.5 mM SDS, meaning that SDS adsorption to the wall was suppressed by the hydrophobic container. Therefore, the octanol system in a hydrophobic container enabled us to elucidate the electrical oscillation without any influence from the wall effect. (c) 2006 Elsevier Inc. All rights reserved.

    DOI PubMed CiNii

  • Technical evaluation of dialysate flow in a newly designed dialyzer

    Ken-Ichiro Yamamoto, Hiroaki Matsukawa, Taiji Yakushiji, Makoto Fukuda, Tatsuo Hiyoshi, Kiyotaka Sakai

    ASAIO JOURNAL   53 ( 1 ) 36 - 40  2007.01

     View Summary

    Rexeed was developed by Asahi Kasei Medical using wave-shaped hollow fibers, a full baffle, and a short taper housing to improve dialysate flow. The present study is clarifies improvement in dialysate flow with Rexeed-15 compared with that of a conventional dialyzer. Dialysate flow was evaluated by the pulse-response method. Dialysate pressure and tracer concentration were measured at a blood-side flow rate (Q(B)) of 200 ml/min, a dialysate-side flow rate (Q(D)) of 500 ml/min, and a net filtration rate (Q(F)) of 0 ml/min using needles placed in the test dialyzer. Dialyzer performance was evaluated by measuring urea and vitamin B-12 clearance at Q(B) = 200 and 400 ml/min, Q(D) = 300-800 ml/min, and Q(F) = 0 ml/min. In the conventional dialyzer, dialysate channeling was observed. In contrast, Rexeed-15 had a uniform dialysate flow. Urea and vitamin B-12 clearance with Rexeed-15 was slightly sensitive to Q(D). The overall mass transfer coefficient for urea with Rexeed-15 was more than 50% higher than that of the conventional dialyzer, indicating the possibility of reduced dialysate usage with Rexeed. Rexeed has a highly optimal dialysate flow, due to the wave-shaped hollow fibers and the new housing, and gives increased clearance for lower-molecular-weight substances.

    DOI PubMed CiNii

  • Novel modeling of electrical potential oscillation across a water/octanol/water liquid membrane

    Takehito Ogawa, Hiroshi Shimazaki, Satoka Aoyagi, Kiyotaka Sakai

    JOURNAL OF MEMBRANE SCIENCE   285 ( 1-2 ) 120 - 125  2006.11

     View Summary

    An oscillating electrical potential across a liquid membrane is studied as a model of a biological system. The oscillating potential is caused by repeated surfactant adsorption and desorption at the interface. The surfactant desorption process was simulated using both Fick's diffusion equation and the Langmuir-Hinshelwood equation. A water/octanol/water liquid membrane containing sodium dodecyl sulfate (SDS) was used and the effect of NaCl was studied. Calculations agree closely with experimental results, supporting the validity of the model we propose. Adsorption rate constants were obtained by comparing the experimental and calculated results. The addition of NaCl increased adsorption rate constants and decreased desorption rate constants. Calculations suggest that surfactant desorbs mainly into the octanol phase and this desorption is not affected by the addition of NaCl. The disordering of potential oscillations by NaCl addition may be caused by decreased SDS accumulation in the octanol phase close to the interface. A lower adsorption rate of the surfactant from the octanol phase onto the water/octanol interface leads to an oscillating electrical potential across the liquid membrane. (c) 2006 Elsevier B.V. All rights reserved.

    DOI CiNii

  • Molecular design of biodegradable polymeric micelles for temperature-responsive drug release

    Masamichi Nakayama, Teruo Okano, Takanari Miyazaki, Fukashi Kohori, Kiyotaka Sakai, Masayuki Yokoyama

    JOURNAL OF CONTROLLED RELEASE   115 ( 1 ) 46 - 56  2006.09

     View Summary

    We designed thenno-responsive and biodegradable polymeric micelles for an ideal drug delivery system whose target sites are where external stimuli selectively release drugs from the polymeric micelles. The thermo-responsive micelles formed from block copolymers that were composed both of a hydrophobic block and a thermo-responsive block. Poly(N-isopropylacrylamide-co-N,N-dimethylacrylamide) showing a lower critical solution temperature (LCST) around 40 degrees C was synthesized for the thermo-responsive block, while biodegradable poly(D,L-lactide), poly(epsilon-caprolactone), or poly(D,L-lactide-co-epsilon-caprolactone) was used for the hydrophobic block. By changing both the block lengths of the poly(D,L-lactide)-containing block copolymers, physical parameters such as micelle diameter and critical micelle concentration were varied. On the other hand, the choice of the hydrophobic block was revealed to be critical in relation to both on the thermo-responsive release of the incorporated anticancer drug, doxorubicin, and the temperature-dependent change of the hydrophobicity of the micelles' inner core. One polymeric micelle composition successfully exhibited rapid and thermo-responsive drug release while possessing a biodegradable character. (c) 2006 Elsevier B.V. All rights reserved.

    DOI

  • Superoxide sensors

    Takehiro Miyasaka, Kosuke Endo, Seiichi Mochizuki, Kiyotaka Sakai

    SENSOR LETTERS   4 ( 2 ) 144 - 154  2006.06

     View Summary

    The reactive oxygen species (ROS) have important physiological and protective roles in the maintenance of living systems. However, excessive production of ROS can impact cellular homeostasis and lead to oxidative stress. Superoxide has high reactivity acting as a reductant and an oxidant. Because of the pathophysiological roles of superoxide several methods for its detection have been developed. Spectrophotometric assay is nonspecific for superoxide, which limits its use. Chemiluminescent methods have been used frequently for vascular tissue samples because they are more sensitive than other conventional methods. Fluorescence-based assays have also been widely used in cultured cells and vascular tissues. Electron spin resonance (ESR) spectroscopy, also known as electron paramagnetic resonance (EPR), quantitatively measures superoxide concentration but is less suitable for its in vivo detection. Electrochemical sensors based on cytochrome c reduction or superoxide dismutase (SOD) enzymatic reaction have been developed for real-time monitoring, but lack adequate performance for in vivo superoxide measurement. Newly developed SOD-immobilized superoxide sensors reportedly have satisfactory performance, for in vitro measurement. In this paper, we review superoxide measurement methods from the early spectrophotometric assays to the third generation of electrochemical sensors.

    DOI

  • Evaluation of the activity of endotoxin trapped by a hollow-fiber dialysis membrane

    K Yamamoto, M Matsuda, M Hayama, J Asutagawa, S Tanaka, F Kohori, K Sakai

    JOURNAL OF MEMBRANE SCIENCE   272 ( 1-2 ) 211 - 216  2006.03

     View Summary

    dialysis patients are at risk of amyloidosis attributed to Et. This suggests that Et may affect the blood even if it does not mix with the blood. The objective of the present study is to evaluate the activity of Et trapped by membranes. We made mini modules out of hollow fibers using three different types of membranes and filtered Et solution. The lumen of the hollow fibers was then filled with limulus amebocyte lysate (LAL) for 15 min at 310 K. Et activity was then determined by measuring absorbance of the LAL reagent. The surfaces of test membranes were studied using an atomic force microscope. With polyester polyrner alloy (PEPA), no Et leakage or Et activity was detected in the hollow fibers under any conditions. With polysulfone (PS) and polyether sulfone (PES), no Et leakage was detected under clinical conditions, but Et activity was detected in the hollow fibers. These results show that Et trapped by the inner skin may affect the blood, even if Et does not mix with the blood. Therefore, Et should be trapped by an outer skin or the part somewhat far from the blood which does not contact with the blood directly. (c) 2005 Elsevier B.V. All rights reserved.

    DOI CiNii

  • ずり応力を負荷された透析膜表面構造の観察

    小川貴久, 松田雅人, 山本健一郎, 薬師寺大二, 酒井清孝

    腎と透析 別冊ハイパフォーマンスメンブレン'06 / 東京医学社   61   156 - 159  2006

  • 原子間力顕微鏡を用いたポリスルホン膜表面のタンパク質吸着特性の評価

    松田雅人, 山本健一郎, 薬師寺大二, 酒井清孝, Rehana Afrin, 猪飼篤

    腎と透析 別冊ハイパフォーマンスメンブレン'06 / 東京医学社   61   163 - 166  2006

  • 透析膜に固定化されたビタミンEの抗酸化能の回復

    奥岡眞視, 山本健一郎, 薬師寺大二, 酒井清孝

    腎と透析 別冊ハイパフォーマンスメンブレン'06 / 東京医学社   61   167 - 169  2006

  • ウェーブ状中空糸膜を用いた新しい透析器の評価

    松川裕章, 山本健一郎, 松田雅人, 薬師寺大二, 酒井清孝

    腎と透析 別冊ハイパフォーマンスメンブレン'06 / 東京医学社   61   116 - 118  2006

  • コンピュータシミュレーションによる高性能透析器の性能評価

    岩島重人, 浅野修司, 小堀深, 酒井清孝, 福田誠, 日吉辰夫

    腎と透析 別冊ハイパフォーマンスメンブレン'06 / 東京医学社   61   119 - 121  2006

  • 分子認識素子として分子インプリントポリマーを応用した化学センサ

    服部浩二, 吉見靖男, 酒井清孝

    Chemical SENSORS / 化学センサ研究会   22 ( 3 ) 110 - 115  2006

    CiNii

  • Thermal modulated interaction of aqueous steroids using polymer-grafted capillaries

    N Idota, A Kikuchi, J Kobayashi, Y Akiyama, T Okano

    LANGMUIR   22 ( 1 ) 425 - 430  2006.01

     View Summary

    Poly (N-isopropylacrylamide) (PIPAAm) of controlled molecular weight was densely grafted onto glass capillary lumenal surfaces using surface-initiated atom transfer radical polymerization (ATRP). Temperature-dependent changes of these thermoresponsive brush surfaces with hydrophobic steroids were investigated by exploiting thermoresponsive aqueous wettability changes of the polymer-modified surfaces in microfluidic systems. IPAAm was polymerized on ATRP initiator-immobilized glass surfaces using CuCl/CuCl2/tris(dimethylaminoethyl)amine (Me6TREN) as an ATRP catalyst in water at 25 C. PIPAAm graft layer thickness and its homogeneity on glass surfaces are controlled by changing ATRP reaction time. Aqueous wettability changes of PIPAAm-grafted surfaces responses drastically changed to both grafted polymer layer thickness and temperature, especially at lower temperatures. Temperature-responsive surface properties of these PIPAAm brushes within capillary inner wall surfaces were then investigated using capillary chromatography. Effective interaction of hydrophobic steroids with dehydrated, hydrophobized PIPAAm-grafted capillary surfaces was observed above 30 C without any column packing materials. Steroid elution behavior from PIPAAm-grafted capillaries contrasted sharply with that from PIPAAm hydrogel-grafted porous monolithic silica capillaries prepared by electron beam (EB) irradiation wherein significant peak broadening was observed at high-temperature regardless of sample hydrophobicity factors (log P values), indicating multistep separation modes in coated monolithic silica capillaries. In conclusion, thermoresponsive polymer-grafted capillary inner wall surfaces prepared by ATRP exhibit useful temperature-dependent surface property alterations effective to regulate interactions with biomolecules without requirements for separation bed packing materials within the capillary lumen.

    DOI PubMed CiNii

  • Hollow-fiber blood-dialysis membranes: Superoxide generation, permeation, and dismutation measured by chemiluminescence

    Ken-Ichiro Yamamoto, Kazuyoshi Kobayashi, Kosuke Endo, Takehiro Miyasaka, Seiichi Mochizuki, Fukashi Kohori, Kiyotaka Sakai

    Journal of Artificial Organs   8 ( 4 ) 257 - 262  2005.12

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    The interaction of blood with a material surface results in activation of the body's humoral immune system and the generation of reactive oxygen species (ROS). It has recently become clear that ROS are central to the pathology of many diseases. In this study, we evaluated the superoxide generation, permeation, and dismutation in hollow-fiber dialysis membranes by using 2-methyl-6-p-methoxyphenylethynyl-imidazopyrazinone (MPEC) as a superoxide-reactive chemiluminescence producer and an optical fiber probe to detect the resulting chemiluminescence in the hollow fiber lumen. We measured the superoxide generated when bovine blood leukocytes were brought into contact with dialysis membranes. Superoxide permeation was determined by measuring MPEC chemiluminescence in the hollow fiber lumen using an optical fiber probe. Additionally, superoxide dismutation was evaluated by examining the difference in superoxide permeability for membranes with and without vitamin E coating. Superoxide generation varies for different membrane materials, depending on the membrane's biocompatibility. Superoxide permeability depends on the diffusive permeability of membranes. No marked decrease in superoxide permeability was observed among membrane materials. The superoxide permeability of vitamin E-coated membrane was smaller than that of uncoated membrane. The antioxidant property of vitamin E-coated membranes is hence effective in causing superoxide dismutation. © The Japanese Society for Artificial Organs 2005.

    DOI PubMed CiNii

  • Hollow-fiber blood-dialysis membranes: Superoxide generation, permeation, and dismutation measured by chemiluminescence

    Ken-Ichiro Yamamoto, Kazuyoshi Kobayashi, Kosuke Endo, Takehiro Miyasaka, Seiichi Mochizuki, Fukashi Kohori, Kiyotaka Sakai

    Journal of Artificial Organs   8 ( 4 ) 257 - 262  2005.12

     View Summary

    The interaction of blood with a material surface results in activation of the body's humoral immune system and the generation of reactive oxygen species (ROS). It has recently become clear that ROS are central to the pathology of many diseases. In this study, we evaluated the superoxide generation, permeation, and dismutation in hollow-fiber dialysis membranes by using 2-methyl-6-p-methoxyphenylethynyl-imidazopyrazinone (MPEC) as a superoxide-reactive chemiluminescence producer and an optical fiber probe to detect the resulting chemiluminescence in the hollow fiber lumen. We measured the superoxide generated when bovine blood leukocytes were brought into contact with dialysis membranes. Superoxide permeation was determined by measuring MPEC chemiluminescence in the hollow fiber lumen using an optical fiber probe. Additionally, superoxide dismutation was evaluated by examining the difference in superoxide permeability for membranes with and without vitamin E coating. Superoxide generation varies for different membrane materials, depending on the membrane's biocompatibility. Superoxide permeability depends on the diffusive permeability of membranes. No marked decrease in superoxide permeability was observed among membrane materials. The superoxide permeability of vitamin E-coated membrane was smaller than that of uncoated membrane. The antioxidant property of vitamin E-coated membranes is hence effective in causing superoxide dismutation. © The Japanese Society for Artificial Organs 2005.

    DOI PubMed CiNii

  • Microfluidic valves comprising nanolayered thermoresponsive polymer-grafted capillaries

    N Idota, A Kikuchi, J Kobayashi, K Sakai, T Okano

    ADVANCED MATERIALS   17 ( 22 ) 2723 - +  2005.11

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    Thermally regulated flow control using a thermoresponsive polymer grafted onto surfaces of capillary lumen facilitates rapid, reliable, and repeatable open-close cycles (see Figure). Hydration of the grafted polymer chains on the internal surfaces may increase the microviscosity of the hydration layers at the wall interfaces without physically occluding the lumen, producing complete and reversible on/off flow valving in microchannels under hydrostatic pressures relevant for microfluidics approaches.

    DOI

  • Membrane fouling and dialysate flow pattern in an internal filtration-enhancing dialyzer

    Ken-Ichiro Yamamoto, Michihito Hiwatari, Fukashi Kohori, Kiyotaka Sakai, Makoto Fukuda, Tatsuo Hiyoshi

    Journal of Artificial Organs   8 ( 3 ) 198 - 205  2005.09

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    For efficient removal of large molecular weight solutes by dialysis, several types of internal filtration-enhancing dialyzers (IFEDs) are commercially available. However, in a pressure-driven membrane separation process (i.e., filtration), membrane fouling caused by adhesion of plasma proteins is a severe problem. The objective of the present study is to investigate the effects of internal filtration on membrane fouling based on the membrane's pure-water permeability, diffusive permeability, and sieving coefficient. Hemodialysis experiments were performed with two different dialyzers, IFEDs and non-IFEDs. Local membrane fouling in each dialyzer was evaluated by measuring the pure-water permeability, the diffusive permeability, and the sieving coefficient of native membranes and membranes treated with bovine blood. The effects of packing ratio on dialysate flow pattern were also evaluated by measuring the time required for an ion tracer to reach electrodes placed in the dialyzers. In the IFED, membrane fouling caused by protein adhesion is increased because of enhanced internal filtration only at the early stage of dialysis, and this fouling tends to occur only near the dialysate outlet port. However, enhanced internal filtration has little effect on measured membrane transfer parameters. © The Japanese Society for Artificial Organs 2005.

    DOI PubMed CiNii

  • Fabrication of a cell array on ultrathin hydrophilic polymer gels utilising electron beam irradiation and UV excimer laser ablation

    S Iwanaga, Y Akiyama, A Kikuchi, M Yamato, K Sakai, T Okano

    BIOMATERIALS   26 ( 26 ) 5395 - 5404  2005.09

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    Most of the surface patterning methods currently applied are based on lithography techniques and microfabrication onto silicon or glass substrates. Here we report a novel method to prepare patterned surfaces on polystyrene substrates by grafting ultrathin cell-repellent polymer layers utilising both electron beam (EB) polymerisation and local laser ablation techniques for microfabrication. Polyacrylamide was grafted onto tissue culture polystyrene (TCPS) dishes using EB irradiation. Water contact angles for these PAAm-grafted TCPS surfaces were less than 10 degrees (cos theta = 0.99) with PAAm grafted amounts of 1.6 mu g/cm(2) as determined by ATR/FT-IR. UV excimer laser (ArF: 193 nm) ablation resulted in the successful fabrication of micropatterned surfaces composed of hydrophilic PAAm and hydrophobic basal polystyrene layers. Bovine carotid artery endothelial cells adhered only to the ablated domains after pretreatment of the patterned surfaces with 15 mu g/mL fibronectin at 37 degrees C. The ablated domain sizes significantly influenced the number of cells occupying each domain. Cell patterning functionality of the patterned surfaces was maintained for more than 2 months without loss of pattern fidelity, indicating that more durable cell arrays can be obtained compared to those prepared by self-assembled monolayers of alkanethiols, as described in previous reports. The surface fabrication techniques presented here can be utilised for the preparation of cell-based biosensors as well as tissue engineering constructs. (c) 2005 Elsevier Ltd. All rights reserved.

    DOI PubMed CiNii

  • Rearrangement of hollow fibers for enhancing oxygen transfer in an artificial gill using oxygen carrier solution

    K Nagase, F Kohori, K Sakai, H Nishide

    JOURNAL OF MEMBRANE SCIENCE   254 ( 1-2 ) 207 - 217  2005.06

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    Using the derived mass transfer correlations for hollow fibers, hollow fiber arrangements were optimized for an artificial gill that uses an oxygen carrier solution. FC-40, a perfluorocarbon (PFC), was used as the oxygen carrier solution. In the oxygen uptake module, a hollow fiber arrangement with parallel coiled hollow fibers is preferred. The optimum outside diameter of the hollow fibers and the transverse pitch between them are 300 and 500 μ m. respectively. In the oxygen release module, a hollow fiber arrangement of straight parallel hollow fibers is preferred. The optimum outside diameter of the hollow fibers and transverse pitch between them are 300 and 500 μ m, respectively. In the case of humans, the scaling up was estimated from the oxygen transfer rates using these optimum hollow fiber arrangements. The required total membrane surface area is 50.8 m(2), the total delivered pumping energy is 124 W, and the oxygen partial pressure in inspiration is 17.8 kPa. Importantly, the total membrane surface area required was significantly reduced using the modules with an optimum hollow fiber arrangement in comparison with that using connected membrane oxygenators as a gas exchanger. The optimization of hollow fiber arrangements in an artificial gill significantly enhances oxygen transfer from water to air. © 2005 Elsevier B.V. All rights reserved.

    DOI

  • Oxygen transfer performance of a membrane oxygenator composed of crossed and parallel hollow fibers

    K Nagase, F Kohori, K Sakai

    BIOCHEMICAL ENGINEERING JOURNAL   24 ( 2 ) 105 - 113  2005.06

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    We have evaluated the mass transfer performance of four commercially available membrane oxygenators in which the blood path is external to and approximately perpendicular to the fiber bundle. Water flowed outside the hollow fibers as an oxygen carrier medium and substitution for blood, and nitrogen gas flowed inside the hollow fibers. The oxygen transfer rates in the membrane oxygenators were measured, and their mass transfer coefficients were obtained. When we analyzed the mass transfer performance using the theory of heat transfer across tube banks, the Sherwood numbers were obviously divided into two regions; one was the data for parallel hollow fibers, and the other was the data for crossed hollow fibers. This indicates that the mass transfer performance of the membrane oxygenator is attributable to the hollow fiber arrangement namely, parallel and crossed hollow fibers, in the same manner as that for heat transfer across tube banks (staggered and in-line bank). New mass transfer correlations have been developed for the membrane oxygenators composed of parallel hollow fibers and crossed hollow fibers. These mass transfer correlations may be used as a guide for the design of a new and efficient membrane oxygenator. (c) 2005 Elsevier B