Ag/TiO2 Nanocomposite Modified Carbon Paste Electrode used to Differential Pulse Voltammetric Determination of Carbamazepine

Ag/TiO2 nanocomposite was used as a modifier in carbon-paste electrode (CPE) to fabricate a carbamazepine (CBZ) voltammetric sensor. The results show an efficient catalytic activity of the electrooxidation of CBZ. Electrochemical behaviour of CBZ at the sensor was studied by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Results showed that the modified electrode exhibited a strong electrocatalytic activity toward the redox of CBZ. The effects of scan rate and pH on peak current were investigated and an optimal scan rate of 50 mV s-1 and a pH 2.0, Britton-Robinson buffer solution (BR), were used. Under the optimum conditions, the catalytic peak currents of CBZ were linearly dependent on the concentrations of CBZ in the range from 2.5×10-6 to 1.0×10-4 mol L-1 with a detection limit of 8.6×10-7 mol L-1. This proposed method was successfully applied to determine the carbamazepin concentration in its tablet as real sample and a recovery of 95% was obtained without interference from tablet matrix.