Direct electrochemistry of horseradish peroxidase on graphene-modified electrode for electrocatalytic reduction towards H2O2

作者：Li, Maoguo; Xu, Shudong; Tang, Min; Liu, Lin; Gao, Feng; Wang, Yinling^*

来源：Electrochimica Acta, 2011, 56(3): 1144-1149.

DOI：10.1016/j.electacta.2010.10.034

• Graphene
• Horseradish peroxidase
• Direct electrochemistry
• Electrocatalysis
• Biosensors

Graphene was synthesized by a chemical method to reduce graphite oxide and well characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), powder X-ray diffraction (PXRD) and Fourier transform infrared (FTIR) spectra. Horseradish peroxidase (HRP) immobilized on a graphene film glassy carbon electrode was found to undergo direct electron transfer and exhibited a fast electron transfer rate constant of 4.63 s(-1). The HRP-immobilized electrode was investigated by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The CV results showed that the modified electrode gave rise to well-defined peaks in phosphate buffer, corresponding to the electrochemical redox reaction between HRP-Fe(III) and HRP-Fe(II). The obtained electrode also displayed an electrocatalytic reduction behavior towards H2O2. The new H2O2 sensor shows a linear range of 0.33-14.0 mu M (R-2 = 0.9987) with a calculated detection limit of 0.11 mu M (SIN = 3). Furthermore, the biosensor exhibits both good operational storage and storage stability.

• 出版日期2011-1-1
• 单位安徽师范大学