A soft-template nanostructured peroxidase based on cytochrome c and sodium decyl sulfate and its electrochemical properties on hydroxyl fullerenes modified glassy carbon electrode

A high catalytic efficient soft-template nanostructured peroxidase (SP) was constructed when cytochrome c (Cyt c, 10 mu M) was mixed with sodium decyl sulfate (SDeS, 40 mM) in 100 mM sodium phosphate buffer solution (PBS). The electrochemical investigations were carried out for the SP immobilized on hydroxyl fullerenes modified glassy carbon electrode (GCE). The cyclic voltammetry of the SP-modified GCE showed a pair of well-defined redox peaks with a formal potential (E degrees') of -220 +/- 2 mV (vs. Ag/AgCl) in 100 mM, pH 8.0 PBS at a scan rate of 0.05 Vs(-1). The heterogeneous electron transfer rate constant (k(S)) was calculated to be 14.3 +/- 1 s(-1). The apparent Michaelis-Menten constant (K-m(app)) was 1.79 +/- 0.03 mu M. SDeS and Cyt c may be important for the structure and catalytic function of SP, respectively. The SP-modified GCE could be used as an H2O2 biosensor instead of horseradish peroxidase (HRP), with good sensitivity and stability.