Direct electrochemical behavior of cytochrome c, and its determination on phytic acid modified electrode

Phytic acid (PA) with its unique structure was attached to a glassy carbon electrode (GCE) to form PA/GCE modified electrode which was characterized by electrochemical impedance. The electrochemical behavior of cytochrome c (Cyt c) on the PA/GCE modified electrode was explored by cyclic voltammetry and differential pulse voltammetry. The Cyt c displayed a quasi-reversible redox process on PA modified electrode pH 7.0 phosphate buffer solution with a formal potential (E (0')) of 57 mV (versus Ag/AgCl). The peak currents were linearly related to the square root of the scan rate in the range of 20-120 mV center dot s(-1). The electron transfer rate constant was determined to be 12.5 s(-1). The PA/GCE modified electrode was applied to the determination of Cyt c, in the range of 5 x 10(-6) to 3 x 10(-4) M, the currents increase linearly to the Cyt c concentration with a correlation coefficient 0.9981. The detection limit was 1 x 10(-6) M (signal/noise = 3).