Electropolymerisation of DL-methionine at Carbon Paste Electrode and its Application to the Determination of Catechol and Hydroquinone

The poly(methionine) modified carbon paste electrode (MCPE) was fabricated for the electroanalysis of catechol (CC) and hydroquinone (HQ) in phosphate buffer solution (PBS) of pH 7.4 by cyclic voltammetric (CV) and differential pulse voltammetric (DPV) techniques. The modified electrode shows selective and sensitive response for the simultaneous determination of CC and HQ in a binary mixture. The peak to peak separation of CC and HQ was 0.115 V and 0.112 V by CV and DPV techniques respectively. The effect of concentration and scan rate reveals the electrode process was controlled by the adsorption of the analytes. This study provides a new method for the modification of working electrode for the voltammetric determination of the CC and HQ.