Fabrication of a covalent organic framework and its gold nanoparticle hybrids as stable mimetic peroxidase for sensitive and selective colorimetric detection of mercury in water samples

Wei Li; Yang Li; Hai-Long Qian; Xu Zhao; Cheng-Xiong Yang; Xiu-Ping Yan

doi:10.1016/j.talanta.2019.05.086

Fabrication of a covalent organic framework and its gold nanoparticle hybrids as stable mimetic peroxidase for sensitive and selective colorimetric detection of mercury in water samples

Talanta. 2019 Nov 1:204:224-228. doi: 10.1016/j.talanta.2019.05.086. Epub 2019 May 24.

Authors

Wei Li¹, Yang Li¹, Hai-Long Qian², Xu Zhao², Cheng-Xiong Yang¹, Xiu-Ping Yan³

Affiliations

¹ College of Chemistry, Research Center for Analytical Sciences, Tianjin Key Laboratory of Molecular Recognition and Biosensing, Nankai University, 94 Weijin Road, Tianjin, 300071, China.
² State Key Laboratory of Food Science and Technology (Jiangnan University), International Joint Laboratory on Food Safety, Institute of Analytical Food Safety, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.
³ State Key Laboratory of Food Science and Technology (Jiangnan University), International Joint Laboratory on Food Safety, Institute of Analytical Food Safety, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, China. Electronic address: xpyan@jiangnan.edu.cn.

PMID: 31357286
DOI: 10.1016/j.talanta.2019.05.086

Abstract

Gold nanoparticles (AuNPs) without surface capping agents are easily aggregated owing to their high surface energy, leading to an unexpected decrease of their catalytic activity. Herein, we report gold nanoparticles decorated covalent organic framework (COF) as mimetic peroxidase for colorimetric detection of mercury. 1,3,5-Tris-(4-formyl-phenyl)triazine (PT) and 4, 4'-azodianiline (Azo) was employed as the monomers to prepare a novel imine based COF PTAzo under solvothermal conditions. AuNPs are further decorated into the PTAzo to form COF-AuNPs hybrid via a citrate reducing method. The COF-AuNPs show high stability, and exhibits enhanced peroxidase mimetic activity in the presence of Hg²⁺. The Hg²⁺ concentration dependent peroxidase mimetic activity of COF-AuNPs enables the development of a sensitive and selective method for detection of Hg²⁺ in aqueous solution. The developed method gives good linearity in the range of 5-300 nM with the limit of detection of 0.75 nM. The results show that Hg²⁺-enhanced peroxidase mimetic activity of COF-AuNPs offers great potential for the detection of Hg²⁺ in real samples.

Keywords: AuNPs; Colorimetric detection; Covalent organic frameworks; Hg(2+); Mimetic peroxidase.