Electrochemically monitoring the removal of bisphenol A based on its anodic deposition at an ITO electrode

In this paper, bisphenol A (BPA) was successfully deposited on an indium–tin oxide (ITO) electrode by the method of multiple sweep voltammetry. The BPA deposition was found to be affected by the upper potential limit of the multiple sweep voltammetry, the voltammetric sweep number, pH value and BPA concentration. The resulting BPA deposit showed excellent redox activity in an appropriate potential range between −0.2 V and 0.4 V as well as high ionic–electronic conductivity, revealed by ex-situ voltammetry and scanning electrochemical microscopy. On the basis of redox reactions of the BPA deposit on the ITO electrode, an electrochemical sensor for monitoring the removal of BPA was further proposed. The linear response range was found to be between 0.5 μM and 50 μM with a detection limit of 0.4 μM (S/N = 3). The results from this study have provided an alternative in situ method for monitoring of BPA removal.