Design of nanogold electrochemical immunosensor for detection of four phenolic estrogens

Abstract

In this paper, using a indirect competitive immunoassay, a electrochemical immunosensor based on hexestrol (HEX)-2-aminoethanethiol hydrochloride (AET)-gold nanoparticles (Au NPs)-glassy carbon electrode (GCE) was favorably prepared to simultaneous detection four phenolic estrogens: HEX, diethylstilbestrol (DES), dienestrol (DE) and bisphenol A (BPA). The HEX-AET-Au NPs-GCE was characterized by scanning electron microscopy (SEM), infrared spectrum (IR) and electrochemical impedance spectroscopy (EIS). A design strategy of HEX-AET-Au NPs-GCE was introduced by nano-sized effect, self-assembly and specific immune technology. The amperometric response sequence was DES > DE > BPA > HEX by differential pulse voltammetry (DPV) with detection limits of 0.25, 0.15, 0.20 and 0.25 ng⋅mL−1, respectively (S/N = 3), which indicates satisfactory linear range and selectivity. Compared with HPLC-MS/MS method, the accuracy of DE detection in real samples was carried out by the HEX-AET-Au NPs-GCE, which displays potential applications in phenolic estrogens detection of environment and food.