reactive hydrogen peroxide biosensor based on self-assembled films of horseradish peroxidase / Laponite / Chitosan and primary research on the inhibitory effect of sulfide

Year of Publication: 2010
Source: and Bioelectronics, in press, accepted employment, available online July 22, 2010
Dan Shan, Li Qing-Bo, Shu-Nian, Ding, Jia Qi, Xu, Serge, Cosnier. . .
horseradish peroxidase (HRP) has been incorporated successfully in Laponite / Chitosan (Chit)-modified glassy carbon electrode (GCE) using step self-assembly. The self-assembly process was monitored by spectroscopy, X-ray photoelectron (XPS) and electrochemical impedance spectra (EIS). Direct electrochemistry and electrocatalysis of self-assembled HRP were studied. Cyclic voltammetry of HRP / Laponite / Chit / GCE in anaerobic phosphate buffer (0. 025M PBS, pH 7. 0), shows a pair of peaks and quasi-reversible equilibrium potential Epa = 0. 024V and CPE =- 0. 132 V vs SCE, attributed to the HRP-Fe (III) / HRP-Fe (II) redox couple. The electrochemical reaction of HRP / Laponite / Chit / GCE exhibits a process of controlled surface electrodes. The electron transfer rate constant was estimated at 1. 82s-1. Self-assembled HRP. . .