Mechanistic and electrochemical investigation of catechol oxidation in the presence of thioacetamide: application for voltammetric determination of thioacetamide in aqueous media

Electrochemical oxidation of catechol has been studied in the presence of thioacetamide (TAM) in a phosphate buffer solution (0.2 mol L-1, pH=6.0) at the surface of glassy carbon electrode by means of cyclic voltammetry. After the cyclic voltammetric investigation of the reaction mechanism of TAM with catechol, TAM has been determinated by means of the differential pulse voltammetry technique. The results showed that the cathodic peak current of catechol reduced in the presence of various concentrations of TAM and that catechol can participate in a 1,4-Michael addition reaction with TAM under an EC mechanism. The decreasing of the cathodic current of catechol showed a linear relationship with the TAM concentration that can be used for the determination of TAM with a detection limit less than 3 mu mol L-1.