Abstract:In this study, an electrochemical, graphene-based biosensor was developed for rapid detection of trace amounts of bisphenol A (BPA). Graphene was prepared by chemical reduction, and its structure and morphology were characterized by using transmission electron microscopy and selected area electron diffraction. Subsequently, graphene, tyrosinase, and chitosan were mixed in an optimized ratio to construct the graphene-tyrosinase–chitosan-modified electrode. Cyclic voltammetry showed that the modified electrode had good electrochemical characteristics. When tested with 0.1 mol?L-1 phosphate buffered saline (pH 7.0), a wide response range for the detection of BPA was obtained with this biosensor, with a low detection limit. The linear range was from 7.5 × 10-8 to 2.5 × 10-6 mol?L-1, the correlation coefficient R2 was 0.996, and the detection limit was 2.18 × 10-8 mol?L-1 (S/N = 3). The results of the stability, reproducibility, and interference tests indicated that the enzyme biosensor prepared in this study exhibited good stability, reproducibility, and high specificity for the detection of BPA. This study provides a sensitive, rapid, and simple method to detect BPA residues.
