Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7140427 | Sensors and Actuators B: Chemical | 2018 | 8 Pages |
Abstract
Owing to the high toxicity of lead (II) (Pb2+) and silver (I) ions (Ag+) to aquicolous organisms, it is highly desirable to develop a sensitive method for the simultaneous detection of Pb2+ and Ag+. In this work, a novel and sensitive single-labeled fluorescent oligonucleotide (OND) probe is designed to simultaneously detect based on the specific complexation of Ag+ to cytosines, the special induction capacity of Pb2+ to guanine-rich OND to form G-quadruplex and the inherent quenching ability of G-quadruplex to the hexachloro fluorescein (HEX). The Ag+-induced hairpin-link structure makes HEX labeled at the 5â²-termini close to the Pb2+-induced G-quadruplex connected at the 3â²-terminin, resulting in a remarkable fluorescence quenching owing to photoinduced electron transfer (PET) process from G-quadruplex to HEX. At 298â¯K, the apparent associating constant between them is 1.85â¯Ãâ¯108 (L/mol). Using this system, we can simultaneously detect the Pb2+ and Ag+ over the linear response range of 1-100â¯nmol/L with a detection limits of 96â¯pmol/L and 21â¯pmol/L, respectively. Through the assay in real samples, it is known that this system could be applied to accurately monitor the trace Pb2+ and Ag+ in aqueous solution.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Yeli Zhang, Wenhua Chen, Xiaoting Dong, Hui Fan, Xiaohua Wang, Liujiao Bian,