Direct electrochemistry of Cytochrome c on natural nano-attapulgite clay modified electrode and its electrocatalytic reduction for H2O2

作者：Xu Ji ming^*; Li Wei; Yin Qi fan; Zhu Yu lan

来源：Electrochimica Acta, 2007, 52(11): 3601-3606.

DOI：10.1016/j.electacta.2006.10.020

• attapulgite clay
• Cytochrome c
• direct electron transfer
• hydrogen peroxide

Natural nano-structural attapulgite clay was purified by mechanical stirring with the aid of ultrasonic wave and its structure and morphology was investigated by XRD and transmission electron microscopy (TEM). Cytochrome c was immobilized on attapulgite modified glassy carbon electrode. The interaction between Cytochrome c and attapulgite clay was examined by using UV-vis spectroscopy and electrochemical methods. The direct electron transfer of the immobilized Cytochrome c exhibited a pair of redox peaks with formal potential (E-0') of about 17 mV (versus SCE) in 0.1 mol/L, pH 7.0, PBS. The electrode reaction showed a surface-controlled process with the apparent heterogeneous electron transfer rate constant (k(s)) of 7.05 s(-1) and charge-transfer coefficient (alpha) of 0.49. Cytochrome c immobilized on the attapulgite modified electrode exhibits a remarkable electrocatalytic activity for the reduction of hydrogen peroxide (H2O2). The calculated apparent Michaelis-Menten constant (K-m(app)) was 470 mu mol/L, indicating a high catalytic activity of Cytochrome c immobilized on attapulgite modified electrode to the reduction of H2O2. Based on these, a third generation of reagentless biosensor can be constructed for the determination of H2O2.

• 出版日期2007-3-1
• 单位淮阴师范学院; 延边大学