Gold Nanoparticle-Modified Molecularly Imprinted Polymer-Coated Pencil Graphite Electrodes for Electrochemical Detection of Bisphenol A.

The sensitive Bisphenol A (BPA) detection by an electrochemical sensor based on gold nanoparticle-doped molecularly imprinted polymer was successfully improved. This study describes the development of a method for BPA detection in both aqueous solution and real water samples using N-methacroyl-(L)-cysteine methyl ester and N-methacryloyl-(L)-phenylalanine methyl ester coated pencil graphite electrodes modified with AuNPs by differential pulse voltammetry (DPV). Importantly, AuNPs, which increase the electroactivity, were used to increase the surface area of a BPA-imprinted pencil graphite electrode (MIP PGE) sensor. Scanning electron microscopy and spectrophotometry analysis were used for the characterization. The DPV response of the synthesized electrode showed distinguished electrical conductivity. The MIP PGE and nonimprinted pencil graphite electrode (NIP PGE) sensor were evaluated for selective and sensitive detection of BPA in aqueous solutions. Five different BPA concentrations (1.5, 3.0, 4.5, 6.0, and 7.5 μM) were applied to the MIP PGE, and the DPV recognized signal responses with a correlation coefficient value of 0.9965. The modified electrode demonstrated good electrocatalytic activity toward BPA for the linear concentration range of 1.5-7.5 μM, and a low limit of detection was found as 0.1610 μM. The results show that the MIP PGE sensor has excellent potential for selective and sensitive detection of BPA in real water samples.