An amperometric biosensor based on a composite of single-walled carbon nanotubes, plasma-polymerized thin film, and an enzyme

Hitoshi Muguruma, Yu Shibayama, Yasunori Matsui

研究成果: Article

54 引用 (Scopus)


We report on an amperometric biosensor that is based on a nanocomposite of carbon nanotubes (CNT), a nano-thin plasma-polymerized film (PPF), and glucose oxidase (GOx) as an enzyme model. A mixture of the GOx and a CNT film is sandwiched with 10-nm-thick acetonitrile PPFs. Under PPF layer was deposited onto a sputtered gold electrode. To facilitate the electrochemical communication between the CNT layer and GOx, CNT was treated with nitrogen or oxygen plasma. The resulting device showed that the oxidizing current response due to enzymatic reaction was 4-16-fold larger than that with only CNT or PPF, showing that the PPF and/or plasma process is an enzyme-friendly platform for designing electrochemical communication from the reaction center of GOx to the electrode via CNTs. The optimized glucose biosensor showed high sensitivity (sensitivity of 42 μA mM-1 cm-2, correlation coefficient of 0.992, linear response range of 0.025-2.2 mM, and a detection limit of 6 μM at signal/noise ratio of 3, +0.8 V versus Ag/AgCl), high selectivity (almost no interference by 0.5 mM ascorbic acid) for glucose quantification, and rapid response (<4 s to reach 95% of maximum response). Additionally, the devices showed a small and stable background current (0.35 ± 0.013 μA) compared with the glucose response (ca. 10 μA at 10 mM glucose) and suitable reproducibility from sample-to-sample (<3%, n = 4).

ジャーナルBiosensors and Bioelectronics
出版物ステータスPublished - 2008 1 18


ASJC Scopus subject areas

  • Biotechnology
  • Biophysics
  • Biomedical Engineering
  • Electrochemistry