Article ID Journal Published Year Pages File Type
7141660 Sensors and Actuators B: Chemical 2018 20 Pages PDF
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.
Related Topics
Physical Sciences and Engineering Chemistry Analytical Chemistry
Authors
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