文献类型：期刊文献

英文题名：A peroxidase-mimicking nanosensor with Hg2+-triggered enzymatic activity of cysteine-decorated ferromagnetic particles for ultrasensitive Hg2+ detection in environmental and biological fluids

作者：Niu, Xiangheng[1];He, Yanfang[1];Li, Xin[1];Zhao, Hongli[2];Pan, Jianming[1];Qiu, Fengxian[1];Lan, Minbo[2]

机构：[1]Jiangsu Univ, Inst Green Chem & Chem Technol, Sch Chem & Chem Engn, Zhenjiang 212013, Peoples R China;[2]East China Univ Sci & Technol, Shanghai Key Lab Funct Mat Chem, Sch Chem & Mol Engn, Shanghai 200237, Peoples R China

年份：2019

卷号：281

起止页码：445

外文期刊名：SENSORS AND ACTUATORS B-CHEMICAL

收录：;EI(收录号：20184406027435);WOS:【SCI-EXPANDED(收录号:WOS:000455021500055)】；

基金：This work was carried out with the supports from the National Natural Science Foundation of China (Nos. 21605061, 31601549 and 21574091), the Natural Science Foundation of Jiangsu Province (Nos. BK20160489 and BK20160056), the Natural Science Fund for Colleges and Universities in Jiangsu Province (No. 16KJB150009), the Postdoctoral Fund of China (No. 2016M600365), the Postdoctoral Fund of Jiangsu Province (No. 1601015B), the Open Fund from the Shanghai Key Laboratory of Functional Materials Chemistry (No. SKLFMC201601), the Open Fund from the State Key Laboratory of Bioreactor Engineering, and the Cultivation Project for Excellent Young Teachers in Jiangsu University.

语种：英文

外文关键词：Cysteine-modified Fe3O4; Biomimetic peroxidase; Hg2+; Stimulus-responsive activity; Ultrasensitive sensing

摘要：In this work, we developed a novel strategy for ultrasensitive Hg2+ detection based on the Hg2+-triggered peroxidase-mimicking activity of a cysteine-decorated ferromagnetic particle (Cys-Fe3O4). The as-synthesized Cys-Fe3O4 exhibited almost no peroxidase-like activity due to the Cys-Fe coordinative interaction and subsequently blocking of active sites on Fe3O4 by the Cys outerwear. In contrast, in the presence of Hg2+, surface Cys could be despoiled from the Cys-Fe3O4 particles by a stronger Cys-Hg2+-Cys coordination, resulting in the exposure of active Fe3O4 that could catalyze the oxidation of colorless 3,3', 5,5'-tetramethylbenzidine (TMB) into blue TMBox. The Cys-Fe3O4 particles were then employed to fabricate a colorimetric Hg2+ nanosensor. We found that the fabricated enzyme-mimicking biosensor enabled to monitor Hg2+ in a linear range of 0.02-90 nM, providing a limit of detection down to 5.9 pM. The enzyme-mimetic nanosensor also exhibited excellent selectivity for Hg2+ sensing against other common metal ions thanks to the strong coordinative interaction between Cys and Hg2+. Further, the nanosensor was applied to determine trace Hg2+ in environmental and biological fluids. Despite the relatively complex components of these samples, the enzyme-like biosensor still showed excellent accuracy, demonstrating its great promise in environmental monitoring and clinical examination.