Alkyl chain length effect on the horseradish peroxidase-catalytic reduction of hydrogen peroxide mediated by methylene blue at alkanethiol self-assembled monolayer electrodes
Zb. Qian et al., Alkyl chain length effect on the horseradish peroxidase-catalytic reduction of hydrogen peroxide mediated by methylene blue at alkanethiol self-assembled monolayer electrodes, BIOELECTR B, 46(2), 1998, pp. 193-198
Horseradish peroxidase (HRP) catalytic reduction of H2O2 mediated by methyl
ene blue (MB) at alkanethiol self-assembled monolayer electrodes (SAME) was
chosen as a model to study the alkyl chain length effect on the electron t
ransfer rate of MB and the electro-HRP-catalytic reduction of H2O2 in this
work. Proper chain length of alkanethiol and scan rate were selected to ach
ieve quasi-reversible reduction of MB. Cyclic voltammetry (CV) results show
ed that the standard electron transfer rate constant of MB at SAME decrease
s exponentially with the alkyl chain length of alkanethiol, meanwhile the h
alf-peak potential of electroenzymocatalytic voltammogram increases linearl
y with the chain length, which is consistent with the theory of Nicholson a
nd Shain. The method combining diffusion mediator with SAME would provide a
new way to analyze electroenzymocatalyzed reaction. (C) 1998 Elsevier Scie
nce S.A. All rights reserved.