Self-powered photoelectrochemical aptasensor for fumonisin B1 detection based on a Z-scheme ZnIn₂S₄/WO₃ photoanode

The incidence of esophageal cancer is positively associated with fumonisin contamination. It is necessary to develop methods for the rapid detection of fumonisins. In this work, a self-powered photoelectrochemical aptamer sensor based on ZnIn₂S₄/WO₃ photoanode and Au@W-Co₃O₄ photocathode is proposed for the sensitive detection of fumonisin B1 (FB1). Among them, under visible light irradiation, the Z-type heterostructure of ZnIn₂S₄/WO₃ acts as a photoanode to improve the electron transfer rate, which contributes to the enhancement of the photocathode signal and lays the foundation for a wider detection range. The Au@W-Co₃O₄ photocathode as a sensing interface reduces the probability of false positives (comparison of anode sensing platforms). The PEC sensor has a good working performance in the detection range (10 pg/mL-1000 ng/mL) with a detection limit of 2.7 pg/mL (S/N = 3). In addition, the sensor offers good selectivity, stability and excellent recoveries in real sample analysis. This work is expected to play a role in the field of analyzing environmental toxins.