ELECTROCATALYSIS OF NADH OXIDATION WITH ELECTROPOLYMERIZED FILMS OF NILE-BLUE-A

A stable electroactive thin film of poly(nile blue A) (PNB) has been d eposited on the surface of a glassy carbon electrode by cyclic voltamm etry in an aqueous solution containing nile blue A (NB). Cyclic voltam mograms of PNB indicate the presence of two redox couples and the form al potential shifts toward negative direction with increasing solution pH. The PNB modified glassy carbon electrode shows excellent electroc atalytic activity toward NADH oxidation in phosphate buffer solution ( pH 6.8), with an overpotential which is more than 660 mV lower than th at of the bare electrode. The catalytic rate constant of the modified glassy carbon electrode for the oxidation of NADH is determined by cyc lic voltammetry and rotating disk electrode measurements.