Direct electron transfer between tyrosinase and multi-walled carbon nanotubes for bioelectrocatalytic oxygen reduction
- 作者：Bertrand Reuillard ; Alan Le Goff ; Charles Agnè ; s ; Abdelkader Zebda ; Michael Holzinger ; Serge Cosnier ; serge.cosnier@ujf-grenoble.fr
- 关键词：Carbon nanotubes ; Multi-copper enzymes ; Tyrosinase ; Direct electron transfer ; Biofuel cells ; Oxygen reduction
- 刊名：Electrochemistry Communications
- 出版年：2012
- 期刊代码：29_13882481
- 类别：ch
- 出版时间：July, 2012
- 卷：20
- 期：Complete
- 页码：19-22
- 文件大小：364 K
摘要
We report the fabrication of a tyrosinase bioelectrode by mechanical compression of a MWCNT enzyme mixture. Cyclic voltammetry of the nanostructured bioelectrode demonstrated a Direct Electron Transfer (DET) process between tyrosinase, a copper enzyme, and MWCNT. The latter led to an enzyme redox potential of + 0.30 V vs SCE, close to the redox potential described for the T3 binuclear copper center. Furthermore, we demonstrate, for the first time, a bioelectrocatalytic reduction of oxygen performed by tyrosinase directly wired within the MWCNT disk. A maximum current density of 0.55 mA cm鈭?#xA0;2 was recorded by chronoamperometric measurements at 0 V vs SCE. The bioelectrode exhibits excellent stability over time, conserving more than 50%of its activity after one week. DET between MWCNTs and the T3 binuclear copper centers have been further investigated by studying the influence of two tyrosinase inhibitors: benzoic acid and cyanide. As previously reported for 鈥渂lue鈥?multicopper oxidases, such as bilirubin oxidase and laccase, tyrosinase can achieve oxygen reduction via DET between MWCNT and its T3 binuclear copper center, representing an alternative in the design of oxygen biocathodes for biofuel cells.