Integrated Nanocomposite Microelectrodes for BPA and E2 Detection: Towards Rapid Estrogenic Disruptor Assessment in Water

ABSTRACT

17β‐Estradiol (E2) and bisphenol A (BPA) widely co‐occur in industrial effluents, plastic manufacturing wastewater, landfill leachates, and polymer systems, typically at nanomolar to micromolar concentrations. The co‐occurrence of BPA and E2 in industrial and hospital wastewater as endocrine disruptors necessitates a rapid, simultaneous detection sensor for assessment. In this study, a silicon‐based microelectrode array is developed for dual electrochemical detection of E2 and BPA on a single platform. The sensor integrates Au–graphitic carbon nitride (gCN) and Au–reduced graphene oxide (Au–rGO) nanocomposites as selective sensing interfaces for E2 and BPA, respectively. Ultrathin gCN nanosheets provide nitrogen‐rich active sites and enhanced surface area for efficient estrogen sensing, while rGO offers high conductivity and defect‐assisted electrocatalytic activity for BPA detection. Unlike single‐analyte sensors optimized for ultra‐trace detection, this platform prioritizes robustness, simplicity, and multi‐analyte capability aligned with environmentally and industrially relevant concentration ranges. With eight independently addressable working electrodes, the platform offers a scalable foundation for multiplexed detection of diverse EDCs, supporting point‐of‐care and in‐field environmental monitoring applications.