Abstract
Abstract Herein we designed a novel photoelectrochemical sensing platform based on Fe3+ doped ZnO-Ag photocatalyst (Fe3+/ZnO-Ag) for ultrasensitive Hg2+ detection by using exonuclease III-assisted target recycling and DNAzyme-catalyzed amplification. Firstly, Fe3+/ZnO-Ag was synthesized to provide photocurrent under visible light irradiation. Secondly, target Hg2+ was determined by hairpin DNA probes on the Fe3+/ZnO-Ag modified ITO based on T-Hg2+-T, and then Hg2+ was released by the digestion of exonuclease III to double-stranded DNA. Finally, the photocurrent markedly decreased due to catalysis of hemin/G-quadruplex toward 4-chloro-1-naphthol. Under optimal conditions, the photocurrents were linearly related to Hg2+ concentrations form 0. 5 nM to 100 nM with a detection limit of 0. 1 nM at the 3Sblank criterion. More importantly, the developed biosensor exhibited good selectivity, repeatability, and stability, meanwhile, this analysis platform held great potential for testing real water samples in future.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have