A visible light-induced self-powered aptasensing platform for kanamycin detection based on mediator-free photofuel cell

Abstract

A visible light-induced self-powered aptasensor for selective detection of kanamycin (KAN) was demonstrated. The sensor was developed on the basis of a photofuel cell (PFC) which was constructed with a graphene-doped BiVO4 (G-BiVO4) photoanode and a Pt cathode in separated chambers. In the designed PFC, the visible light-driven photocatalytic water oxidation on G-BiVO4 photoanode and oxygen reduction on Pt cathode resulted in the generation of electricity. When KAN-binding aptamer was immobilized on G-BiVO4 photoanode as recognition element, the output of the PFC was declined after KAN was captured by aptamer. Under the optimized condition, the output power density of PFC was found to be linearly proportional to the logarithm of KAN concentration ranging from 10 to 500 nM, with a detection limit (3S/N) of 1.0 nM. This mediator-free PFC-based self-powered aptasensor demonstrated a new strategy for sensitive detection of KAN with high selectivity, desirable stability and good reproducibility.