Development of ternary hybrid composites of transition metal and noble metal-based heterostructures: Ultrasensitive simultaneous electrochemical detection of bisphenol A and bisphenol S in food samples

Bisphenols threaten human health and sensitive detection is crucial. The present study aims to develop ternary composites of copper metal-organic framework (Cu-MOF) with Au[sbnd]Ag microstructures. The composite structure was formed by a galvanic displacement reaction and confirmed using SEM. A binder-free catalyst was used to study the electrochemical redox reaction of bisphenol A (BPA) and bisphenol S (BPS); an irreversible cyclic voltammetric signal at +0.70 V and + 0.91 V (vs. Ag/AgCl), in the dynamic range of 20 nM to 2.0 mM, and 10 nM to 1.0 mM, with limits of detection of 2.9 nM, and 3.2 nM (S/N = 3) was obtained. Practical analysis was applied to frozen tomatoes, tuna fish, milk powder, PET bottles, raw milk, and urine samples with a recovery rate of 94.00–100.80% (n = 3). Voltammetric results were validated using HPLC detection with high precision. The sensor is a promising alternative platform for measuring BPA in food samples.