Surfactant-enhanced electrochemical detection of bisphenol A based on Au on ZnO/reduced graphene oxide sensor

Bisphenol A (BPA), one of the most commonly used plastic organic monomers, is widely used in manufacturing food packaging and containers. However, the gradual emissions of BPA from manufacturing plastic products bring great potential in human health threats, which urgently need to develop a simple and rapid method for detecting BPA. Cetyltrimethylammonium bromide (CTAB), a typical surfactant, is used to enhance the electrochemical detection of trace endocrine disruptors due to the fact that it can effectively enrich and absorb hydrophobic phenolic compounds through the hydrophobicity of its long-chain alkanes. Based on these, the present study reports a ternary composite of Au on zinc oxide/reduced graphene oxide nanosheets (Au/ZnO/rGO) as electrochemical sensor for detecting BPA. With the addition of CTAB, the analytic performances toward BPA detection are significantly improved 3.8 times compared with those without CTAB. The pH, accumulation potential and time are optimized. Moreover, the electrochemical activity of CTAB/Au/ZnO/rGO sensor is also evaluated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), differential pulse voltammetry (DPV) and scan rate. The sensor displays two linear range from 10 to 1340 nmol.L-1 and 1340 to 10,000 nmol.L-1, and a low detection limit of 4.95 nmol.L-1. Lastly, the sensor also exhibits good reproducibility, selectivity and potential practical application for BPA detection in real samples.