Development of a self-signaling electrochemical sensor utilizing CoNiFe-PBA for detection of Bisphenol A in food samples.

A self-signaling electrochemical sensor based on molecular imprinting technology for the detection of Bisphenol A (BPA) in food samples. The sensor was constructed through sequential modification of the electrode with reduced graphene oxide (RGO) and CoNiFe Prussian blue analogue (CoNiFe-PBA), followed by electropolymerization of an MIP film using BPA as template and o-phenylenediamine as monomer. CoNiFe-PBA provides an intrinsic signal at ~ 0.47 V without external probes, originating from synergistic redox interactions among Co, Ni, and Fe. BPA rebinding reduces the signal via steric hindrance, enabling sensitive detection in food samples. Under optimal conditions, the sensor demonstrated a wide linear detection range (0.5-500 nM) and a low detection limit (0.19 nM). Owing to its high selectivity, sensitivity, and accuracy, the sensor offers a reliable approach for precise quantification of trace BPA in complex food matrices.