1. Fabrication of a carbon fiber paper as the electrode and its application toward developing a sensitive unmediated amperometric biosensor
- Author
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Teng Yang Wu, Chung Liang Wang, Chiun-Jye Yuan, Kuo Chu Hwang, and Wei Chi Chao
- Subjects
Paper ,Bisphenol ,Nitrogen ,Tyrosinase ,Biomedical Engineering ,Biophysics ,Analytical chemistry ,Biosensing Techniques ,Redox ,chemistry.chemical_compound ,Phenols ,Carbon Fiber ,Electrochemistry ,Detection limit ,Catechol ,Chemistry ,Monophenol Monooxygenase ,Photoelectron Spectroscopy ,General Medicine ,Electrochemical Techniques ,Equipment Design ,Enzymes, Immobilized ,Carbon ,Electrode ,Ferricyanide ,Biosensor ,Biotechnology ,Nuclear chemistry - Abstract
Carbon fiber paper (CFP), a material frequently used as the diffusion layer in fuel cells, was found recently to exhibit a potential as an electrode for the development of sensitive, unmediated biosensors. After nitrogen plasma treatment, the CFP exhibited a quasi-reversible behavior to the redox couple (e.g., ferricyanide) with an electron transfer rate constant of 7.2 × 10(-3)cms(-1). This rate constant is approximately double that of a Pt-electrode and is much higher than that of many carbon-based electrodes. The unmediated CFP-based tyrosinase biosensor fabricated for this study exhibited an optimal working potential and operating pH value of -0.2V and 6.5, respectively. Compared to other unmediated tyrosinase biosensors, the CFP-based tyrosinase biosensor offers a high sensitivity for the monitoring of phenolic compounds (17.8, 7.1, 5.2 and 3.7 μA μM(-1)cm(-2) for catechol, phenol, bisphenol and 3-aminophenol, respectively). The lowest detection limit for catechol, phenol, bisphenol and 3-aminophenol was 2, 5, 5 and 12 nM, respectively. Furthermore, this biosensor exhibited a good repeatability, a fast response time (around 10s), and a wide linear dynamic range of detection for phenolic compounds.
- Published
- 2010