Electrochemical sensing of bisphenol A based on polyglutamic acid/amino-functionalised carbon nanotubes nanocomposite

This study reports the application of polyglutamate acid (PGA) and amino-functionalised carbon nanotube (MWCNT-NH2) nanocomposite modified glassy carbon electrodes for the electrochemical determination of bisphenol A (BPA). The PGA/MWCNT-NH2 nanocomposite exhibits excellent electrocatalytic activity for the oxidation of BPA by substantially enhancing the current response and decreasing the BPA oxidation overpotential. The composite modified glass carbon electrode (GCE) exhibited good performance for detecting BPA due to the enhanced electron transfer kinetics and large active surface area. The effective enrichment of BPA is due to the carboxyl and amino groups on the composite. Under the optimised conditions and according to the results from differential pulse voltammetry (DPV), the BPA oxidation current is linear in a concentration range of 0.1 to 10 μM (R = 0.998), and the detection limit was determined to be 0.02 μM (S/N = 3). The proposed sensors were successfully employed to determine BPA in real plastic products, and the recoveries were between 95% and 108%. This strategy might enable more opportunities for the electrochemical determination of BPA in practical applications.