Abstract
Stable films made from chitosan (CS) on pyrolytic graphite (PG) electrode gave direct electrochemistry for incorporated enzyme nitrate reductase (NR). Cyclic voltammetry (CV) of NR-CS films showed a pair of well-defined and nearly reversible redox peaks at about -0.430 V vs. SCE at pH 7.0 phosphate buffers, which was considered as the redox of FAD and heme-ion. The electron transfer between NR and PG electrode was greatly facilitated in CS films. Integration of reduction peaks at different scan rates from 0.01 to 0.5 V s-1 gave nearly constant charge values, which is characteristic of thin-larger- electrochemical behavior. The pH of the solution strongly affected the direct electron transfer of NR-CS films. EDTA accelerated the electron transfer, and it was proposed as a stimulant for the system. Reflectance absorption infrared spectra demonstrated that NR retained a nearly native conformation in CS films.
Original language | English |
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Pages (from-to) | 59-63 |
Number of pages | 5 |
Journal | Journal of the Chinese Chemical Society |
Volume | 51 |
Issue number | 1 |
DOIs | |
Publication status | Published - Feb 2004 |
Externally published | Yes |
Keywords
- Chitosan
- Cyclic voltammetry
- Nitrate reductase