基于石墨烯-酪氨酸酶-壳聚糖快速检测BPA电化学酶传感器的研究与应用

Nanographene-tyrosinase-chitosan-based Electrochemical Enzyme Biosensor for Rapid Detection of Bisphenol A

摘要:

为了实现双酚A的快速痕量检测，研究制备了一种基于石墨烯的电化学生物传感器。本文通过化学还原法制备了石墨烯，并利用透射电镜(TEM)，选区电子衍射(SAED)对其结构和形貌进行表征。将石墨烯，酪氨酸酶及壳聚糖按照一定优化比例混合，构建了石墨烯-酪氨酸酶-壳聚糖修饰电极(GR-Tyr-CS/GCE)，循环伏安法表明该修饰电极具有良好的电化学特征。在0.1 mol/L的磷酸盐缓冲盐溶液（PBS，pH7.0）中，采用电流-时间法测得该传感器对双酚A的响应范围宽，且检测线低，其检测线性范围为7.5×10-8~2.5×10-6 mol/L，相关系数R2=0.996,检出限为2.18×10-8 mol/L (S/N=3)。由稳定性，重现性及抗干扰性试验结果表明，该酶传感器具有良好的稳定性、重现性及选择专一性，本研究为实际样品中BPA残留提供了灵敏、快速、简便的检测方法。

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.