Curriculum Vitaes

Tomoyuki Yasukawa

  (安川 智之)

Profile Information

Affiliation
Graduate Schoolof Material Science, University of Hyogo
Degree
博士(工学)(東北大学)

J-GLOBAL ID
201801013672318648
researchmap Member ID
B000328123

Papers

 189
  • Kazuki Terao, Masato Suzuki, Ryota Kunikata, Atsushi Suda, Kumi Y. Inoue, Kosuke Ino, Tomokazu Matsue, Tomoyuki Yasukawa
    Sensors and Materials, 35(10) 4781-4781, Oct 25, 2023  
  • Satoko Fujiwara, Misaki Hata, Ikumi Onohara, Daiki Kawasaki, Kenji Sueyoshi, Hideaki Hisamoto, Masato Suzuki, Tomoyuki Yasukawa, Tatsuro Endo
    RSC Advances, 13(31) 21118-21126, Jul 12, 2023  
    Surface plasmon resonance is an optical phenomenon that can be applied for label-free, real-time sensing to directly measure biomolecular interactions and detect biomarkers in solutions. Previous studies using plasmonic nanohole arrays have monitored and detected various biomolecules owing to the propagating surface plasmon polaritons (SPPs). Extraordinary optical transmission (EOT) that occurs in the near-infrared (NIR) and infrared (IR) regions is usually used for detection. Although these plasmonic nanohole arrays improve the sensitivity and throughput for biomolecular detection, these arrays have the following disadvantages: (1) molecular diffusion in the solution (making the detection of biomolecules difficult), (2) the device fabrication's complexities, and (3) expensive equipments for detection in the NIR or IR regions. Therefore, there is a need to fabricate plasmonic nanohole arrays as biomolecular detection platforms using a simple and highly reproducible procedure based on other SPP modes in the visible region instead of the EOT in the NIR or IR regions while suppressing molecular diffusion in the solution. In this paper, we propose the combination of a polymer-based gold nanohole array (Au NHA) obtained through an easy process as a simple platform and dielectrophoresis (DEP) as a biomolecule manipulation method. This approach was experimentally demonstrated using SPP and LSPR modes (not EOT) in the visible region and simple, label-free, rapid, cost-effective trapping and enrichment of nanoparticles (trapping time: <50 s) and bovine serum albumin (trapping time: <1000 s) was realized. These results prove that the Au NHA-based DEP devices have great potential for real-time digital and Raman bioimaging, in addition to biomarker detection.
  • Tomoyuki YASUKAWA, Masato SUZUKI
    Electrochemistry, 91(1) 56-61, Mar 5, 2023  Peer-reviewedInvitedLead authorCorresponding author
  • Masato Suzuki, Shikiho Kawai, Chean Fei Shee, Ryoga Yamada, Seiichi Uchida, Tomoyuki Yasukawa
    Lab on a Chip, 23(4) 692-701, Feb, 2023  Peer-reviewedLast authorCorresponding author
    Simultaneous electrorotation in microwells during chemical stimulation label-free monitoring effect of chemicals in single-cell manner.
  • 安川智之, 鈴木雅登
    表面技術, 73(9) 427-433, Sep, 2022  Peer-reviewedInvitedLead authorCorresponding author

Misc.

 129

Books and Other Publications

 14

Presentations

 174
  • 水谷 文雄, 吉本 有希, 安川 智之
    Proceedings of the Chemical Sensor Symposium, Mar, 2009
  • Kosuke Ino, Yusuke Kitagawa, Hitoshi Shiku, Masahiro Koide, Masahiro Koide, Yoshiko Horiguchi, Tomoaki Itayama, Tomoyuki Yasukawa, Tomokazu Matsue
    Proceedings of Conference, MicroTAS 2009 - The 13th International Conference on Miniaturized Systems for Chemistry and Life Sciences, Jan 1, 2009
    Endocrine disrupting chemicals that act like hormones is a potential hazard for human health. Therefore, it is necessary to develop a device that can detect easily hormone active chemicals. In this study, a microfludic device with some analytical chambers was fabricated for manipulating the yeast cells that were genetically engineered to respond to the presence of hormone active chemicals by synthesizing β-galactosidase (β-gal). Interdigitated array (IDA) electrodes with 40 electrode fingers were incorporated into the device for sensitive detection of the β-gal activity electrochemically, and hormone active chemicals were successfully detected by using the systems. © 2009 CBMS.
  • T. Yasukawa, E. Ohta, Y. Mie, O. Niwa, F. Mizutani
    ECS Transactions, Dec 1, 2008
    A coulometric signal accumulation system to detect a trace concentration of hydrogen peroxide (H2O2) has been applied to develop a novel electrochemical enzyme immunosensing system for insulin, an important hormone for clinical diagnosis of diabetes. Glucose oxidase (GOx)-labeled anti-insulin IgG antibody was trapped on the substrate immobilized with insulin by an indirect competitive immunoassay. H2O2 generated by the enzymatic reaction with the trapped conjugate was detected by the coulometric signal accumulation system. The H2O2 generated oxidized [Os(bpy)2Cl]+ to [Os(bpy)2Cl] 2+ in a horseradish peroxidase (HRP)-containing polymer layer on an electrode under the open-circuit condition, and then the [Os(bpy) 2Cl]2+ accumulated was reduced by applying a negative potential. The accumulation brought about a large current response and a low detection limit for H2O2 (0.5 nM). The enhanced sensitivity for H2O2 enabled the determination of a trace concentration of insulin with the immunoassay using the antibody modified with GOx, a H2O2-producing enzyme. © The Electrochemical Society.
  • Tomoyuki Yasukawa, Tomoyuki Yasukawa, Ramón Azcón Javier, Ramón Azcón Javier, Hitoshi Shiku, Hitoshi Shiku, Fumio Mizutani, Fumio Mizutani, Tomokazu Matsue, Tomokazu Matsue
    2008 International Symposium on Micro-NanoMechatronics and Human Science, MHS 2008, Dec 1, 2008
    Negative dielectrophoresis (n-DEP) have been used to manipulate microparticles with immunoreagents (antigens or antibodies) in a microfluidic channel, and applied to develop a rapid immunoassay system. A microfluidic device, with three-dimensional (3-D) microelectrodes fabricated on two substrates, was used to manipulate particle flow in the channel and to capture the particles in the caged area that was enclosed by the collector electrodes. Polystyrene microparticles (6 μm diameters) modified with anti-mouse immunoglobulin G (IgG) were manipulated and captured in the caged area by using n-DEP. A sandwich immunoassay was achieved by successively injecting a sample solution containing mouse antigen (IgG), and a solution containing FITC-labeled anti-mouse IgG antibody, into the channel. The fluorescence intensity from captured particles in the caged area increased with increasing concentrations (10 ng/ml to 10 μg/ml) of mouse IgG. The described system enables mouse IgG to be assayed in 40 min. This immunosensing system using the n-DEP technique is faster and simpler than conventional enzyme-linked immunosorbent assay (ELISA) using microtiter plates, and has the significant advantage that sensing requires simple and easy handling since unreacted immunomolecules are flushed from the signal detection area by the fluidic stream. The device can be reused by removing the microparticles. The automatic separation of free fractions from desired analytes and labeled antibodies can be achieved using a microfluidic device based on n-DEP. © 2008 IEEE.
  • Lee Hyun Jung, 安川 智之, 珠玖 仁
    Proceedings of the Chemical Sensor Symposium, Sep, 2008
  • 安川 智之, 稲積 伸吾, 品川 真吾
    Proceedings of the Chemical Sensor Symposium, Sep, 2008
  • INO Kosuke, OZAWA Fumisato, YASUKAWA Tomoyuki, Shiku Hitoshi, MATSUE Tomokazu
    日本生物工学会大会講演要旨集, 2008
  • Tomoyuki Yasukawa, Masato Suzuki, Hitoshi Shiku, Tomokazu Matsue
    2007 International Symposium on Micro-NanoMechatronics and Human Science, MHS, Dec 1, 2007
    In this paper, a versatile, rapid and reproducible method for patterning different cell types based on negative dielectrophoresis (n-DEP), without any special pretreatment of a culture slide, has been described. An interdigitated array (IDA) electrode with four independent microelectrode subunits was fabricated with indium-tin-oxide (ITO) and used as a template to form cellular micropatterns. A suspension of C2C12 cells was introduced into the device between the upper slide and the bottom IDA. In the present system, the n-DEP force is induced by applying an ac voltage (typically 12 Vpp, 1 MHz) to direct cells toward a weaker region of electric field strength. The cells aligned above one of the bands of IDA within 1 min since the aligned areas on the slide were regions with the lower electric field. The application of an ac voltage for 5 min allows the cells to adsorb onto the cell culture slide. After disassembling the device and removing excess cells, the culture slide was assembled again with the IDA electrode, and was rotated 90° relative to the previous setup. The second cell type was patterned in lines using the same method as with the first set of cells, forming a grid pattern on the slide. ©2007 IEEE.
  • Hitoshi Shiku, Tomoyuki Yasukawa, Tomokazu Matsue, Takahiro Ito-Sasaki, Masaki Yokoo, Hiroyuki Abe, Shigeo Aoyagi
    Proceedings of IEEE Sensors, Dec 1, 2007
    Scanning electrochemical Microscopy (SECM) has been used to noninvasively characterize oxygen consumption rate of single mammalian embryos and oocytes under physiological condition in culure medium at 37 °C. Local oxygen concentration profile near the embryo sample was monitored by scanning with a Pt microelectrode probe, and then mass transfer rate for oxygen has been estimated based on spherical diffusion theory. A bovine embryo at two-cell stage was located in either a conventional culture dish or a cone-shaped microwell and compared the differences in concentration profile and diffusion behavior. We found that the cone-shaped microwell functions to amplify the oxygen concentration difference between the sample surface and the bulk. Further more, a measuring plate equipped with the cone-shaped six-microwells was developed to easily handle many embryos in a short time. The respiration activities significantly increased with the embryo development for both bovine and mouse. © 2007 IEEE.
  • OKAZAKI Naoto, YOKOO Masaki, ITO SASAKI Takahiro, YASUKAWA Tomoyuki, SHIKU Hitoshi, ABE Hiroyuki, MATSUE Tomokazu
    Journal of mammalian ova research = 日本哺乳動物卵子学会誌, Apr 1, 2007
  • 國方 亮太, 安川 智之, 北川 雄介
    Proceedings of the Chemical Sensor Symposium, Mar, 2007
  • Masato Suzuki, Tomoyuki Yasukawa, Mariko Komabayashi, Akiko Inagaki, Yoshio Hor, Hitoshi Shiku, Tomokazu Matsue
    2006 IEEE International Symposium on Micro-Nano Mechanical and Human Science, MHS, Dec 1, 2006
    Technologies in tissue engineering or regenerative medicine have been applied for various organs and tissues. Some of them have already been clinically applied. However, tissue engineering of the muscle is still difficult. We clarify the difficulties of muscle tissue engineering and discuss the possibility of n-DPE (negative dielectrophresis) application for muscle tissue engineering.
  • SAITO Takeshi, ABE Hiroyuki, YOKOO Masaki, SASAKI Takahiro, HOSHI Hiroyoshi, YASUKAWA Tomoyuki, SHIKU Hitoshi, MATSUE Tomokazu
    Journal of mammalian ova research = 日本哺乳動物卵子学会誌, Apr 1, 2006
  • Masato Suzuki, Tomoyuki Yasukawa, Mariko Komabayashi, Akik Inagaki, Yoshio Hori, Hitoshi Shiku, Tomokazu Matsue
    Micro Total Analysis Systems - Proceedings of MicroTAS 2006 Conference: 10th International Conference on Miniaturized Systems for Chemistry and Life Sciences, Jan 1, 2006
    Biological cells have been manipulated in a microdevice by means of negative dielectrophoresis (n-DEP) to form a micropatterns with two different cell types. The device with interdigitated array (IDA) electrodes was used to manipulate cells and to create a periodical line patterns with cells on a cell culture slide that was placed on 30 μm above IDA electrodes. Mouse myoblast cells (C2C12) were used as model cells to regulate the cultivation in weaker electric field regions in the micropatterning device filled with a cell culture medium. Specifically, cells formed the line pattern within 30 sec on the cell culture slide when a 1 MHz ac voltage (12 Vpeak-to-peak) was applied to the IDA electrodes. Most of patterned cells adsorbed on the slide after several minutes incubation under the application of ac voltage. The micropatterning with alternate lines of two different cell types was achieved by subsequently injecting another cell suspension in the device, and applying ac voltage to a different set of IDA electrodes. The method based on n-DEP permits the quick and easy fabrication of micropatterns composed from two different cell types without chemical modification of substrates. © 2006 Society for Chemistry and Micro-Nano Systems.
  • Kuniaki Nagamine, Tomoyuki Yasukawa, Hitoshi Shiku, Masahiro Koide, Tomosato Itayama, Tomokazu Matsue
    Micro Total Analysis Systems - Proceedings of MicroTAS 2006 Conference: 10th International Conference on Miniaturized Systems for Chemistry and Life Sciences, Jan 1, 2006
    We have fabricated a microfluidic device comprising a 100 pL scale analytical chamber for electrochemical measurement of cellular activities. The microfluidic main channel and the analytical chamber were fabricated using poly(dimethylsiloxane) (PDMS). The chamber contained two Pt microelectrodes served as an electrochemical working electrode and an electrophoretic electrode to manipulate cells into the chamber. Yeast cells were introduced to the chamber by the electrophoresis, and its β-galactosidase (βGal) activities were characterized by amperometry. p-Aminophenol (PAP), generated by the enzyme-catalyzed hydrolysis of p-aminophenyl-β-D-galactopyranoside (PAPG), was detected electrochemically. © 2006 Society for Chemistry and Micro-Nano Systems.
  • NAGAMINE Kuniaki, GOTO Shun, YASUKAWA Tomoyuki, SHIKU Hitoshi, MATSUE Tomokazu
    日本生物工学会大会講演要旨集, 2006
  • 沼井 大輔, 長峯 邦明, 安川 智之
    Proceedings of the Chemical Sensor Symposium, Sep, 2005
  • NAGAMINE Kuniaki, ONODERA Shiho, TORISAWA Yu-suke, YASUKAWA Tomoyuki, SHIKU Hhtoshi, MATSUE Tomokazu
    日本生物工学会大会講演要旨集, 2005
  • 小笠原 大知, 平野 悠, 安川 智之
    Proceedings of the Chemical Sensor Symposium, Mar, 2004
  • 尾形 幸子, 安川 智之, 珠玖 仁
    Proceedings of the Chemical Sensor Symposium, Sep, 2003
  • 安川 智之, Glidle Andrew, 野村 昌行
    Proceedings of the Chemical Sensor Symposium, Apr, 2003
  • 高橋 透, 安川 智之, 尾形 幸子
    Proceedings of the Chemical Sensor Symposium, Apr, 2002
  • 彼谷 高敏, 西澤 松彦, 安川 智之, 丹羽 和裕, 西口 昌志, 小野内 徹, 末永 智一
    バイオイメージング, Nov 1, 2000
  • 安川 智之, 池谷 俊通, 末永 智一
    Proceedings of the Chemical Sensor Symposium, Apr, 2000

Teaching Experience

 5

Research Projects

 64

Industrial Property Rights

 13

Social Activities

 5