Electropreparation of poly(benzophenone-4) film modified electrode and its electrocatalytic behavior towards dopamine, ascorbic acid and nitrite

The oxidation of benzophenone-4 (2-hydroxy-4-methoxybenzophenone-5-sulfonic acid) at glassy carbon electrode gives rise to stable redox active electropolymerized film during repetitive potential cycling between 0 to 1.3 V (Ag/ AgCl). Cyclic voltammogram of poly(benzophenone-4) film shows a redox couple with well-defined peaks. The redox response of the modified electrode was found to be depending on the pH of the contacting solution. The peak potentials were shifted to a less positive region with increasing pH and the dependence of the peak potential was found to be 51 mV/pH. The electrocatalytic behavior of poly(benzophenone-4) film modified electrode towards oxidation of dopamine, ascorbic acid and reduction of nitrite was investigated. The oxidation of dopamine and ascorbic acid occurred at less positive potential on poly(benzophenone-4) film compared to bare glassy carbon electrode. For dopamine, the overpotential was reduced about 180 mV. Feasibility of utilizing poly (benzophenone-4) film coated electrode in analytical estimation of dopamine, ascorbic acid and nitrite was also demonstrated.