Abstract: The preparation of poly(ferulic acid) glassy carbon modified electrode and its electrochemical properties were studied.The modified electrode gives a quasi-reversible redox peaks in 0.1 mol/Lphosphate buffer solution(pH=6.60) over the potential range from -0.1 to 0.5 V(vs.Ag/AgCl), in which the formal potential is 0.188V(vs.Ag/AgCl).The formal potential shifts in a negative direction with the increasing of pHvalues.The electrode reaction contains one electron and one proton.The PFA modified electrode shows an electrocatalytic activity for the oxidation of NADH in 0.1 mol/Lphos phate buffer solution.The apparent electron transfer rate constant(k_s) and transfer coefficient for electron transfer between the electrode surface and immobilized PFA were calculated as 6.6 s^-1and 0.496, respectively, the diffusion coefficient of NADH was calculated as 1.76×10^-6cm²/s by using chronoamperometric results.The peak currents were proportional to the concentrations of NADH in the range of 0.01-5.0 mmol/L.Finally the heterogeneous rate constant for the oxidation of NADHon the PFAmodified electrode surface was also determined and found to be about 6.82×10³ mol^-1·L·s^-1.

Key words: NADH, Ferulic acid, Glassy carbon modified electrode, Electropolymerization, Electrocatalysis