Graphene Decorated with Silver Nanoparticles as Electrocatalytic Labels in Non-Enzymatic Bisphenol-A Immunosensor

This work presents a design of a simple and sensitive sensing interface consisting of a graphene/poly(1,5-diaminonaphthalene) nanocomposite, denoted as Gr/P(1,5DAN), as an immobilization matrix and graphene decorated with silver nanoparticles (Gr-AgNPs) as an electrochemical label for bisphenol A (BPA). The nanocomposite was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electrochemical techniques (CV and EIS). Immunocomplex formation between the anti-BPA antibody (αBPA) and BPA antigen would induce the square wave voltammetric (SWV) peak current variation of Gr-AgNPs labels, and afterward, the concentration of BPA could be indirectly assayed and qualitatively determined. The results indicated a linear relationship between (SWV) response to the BPA concentration in a range of 1.0–8.0 nM, with a limit of detection (LOD) of 0.6 nM. It is a promising attempt for PBA analysis with a low-cost and easy-to-fabricate sensor. Graphic Abstract