Label-free colorimetric sensor for mercury(II) and DNA on the basis of mercury(II) switched-on the oxidase-mimicking activity of silver nanoclusters》.pdfVIP

Analytica Chimica Acta 871 (2015) 1–8 Contents lists available at ScienceDirect Analytica Chimica Acta journa l home page : www.e /locate/aca Label-free colorimetric sensor for mercury(II) and DNA on the basis of mercury(II) switched-on the oxidase-mimicking activity of silver nanoclusters Guang-Li Wang *, Lu-Yi Jin, Xiu-Ming Wu, Yu-Ming Dong, Zai-Jun Li The Key Laboratory of Food Colloids and Biotechnology, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, PR China H I G H L I G H T S G R A P H I C A L A B S T R A C T The oxidase-like activity of BSA-Ag NCs was “switched-on” selectively by Hg2+. 2+ Hg stimulated Ag NCs had a better affinity than HRP considering TMB as a substrate. The triggered enzyme mimicking activity was utilized to colorimetri- cally detect DNA. This colorimetric sensor for DNA was label-free, facile and fast. A R T I C L E I N F O A B S T R A C T Article history: In this paper, a novel colorimetric biosensor for Hg2+ and DNA molecules is presented based on Hg2+ Received 7 December 2014 stimulated oxidase-like activity of bovine serum albumin protected silver clusters (BSA-Ag NCs). Under Received in revised form 6 February 2015 2+ 0 mild conditions, Hg activated BSA-Ag NCs to show high catalytic activity toward the oxidation of 3,3 ,5, Accepted 10 February 2015 0