An Electrochemical Sensor on the Novel MgO-PEDOT:PSS Platform for Sensitive Bisphenol A Determination

A novel magnesium oxide and poly(3,4-ethylenedioxythiophene):poly(styrene-sulfonate) (PEDOT:PSS) composite modified carbon paste electrode (MgO-PP/CPE) has been fabricated for the sensitive quantification of bisphenol A (BPA). The modified electrode was characterized by scanning electron microscopy (SEM), chronocoulometry and electrochemical impedance spectroscopy (EIS). Compared with MgO/CPE, PP/CPE, and CPE, MgO-PP/CPE exhibited enhanced electrochemical activity toward the oxidation of BPA, which was due to the high surface area of MgO and facile electron transfer ability of PEDOT:PSS. Under the optimum conditions, the linear sweep voltammetric oxidation peak current of BPA was linear with its concentration in the ranges from 1.0 nM to 0.4 µM and 0.4 to 10 µM, with a low detection limit of 0.5 nM (3S/N). The fabricated sensor was successively applied to the quantification of BPA content in water samples.