基于石墨相氮化碳的汞（II）荧光猝灭型生物传感器

A "turn-off" fluorescent biosensor for the detection of mercury (II) based on graphite carbon nitride.

机构信息

Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China.

出版信息

Talanta. 2017 Jan 1;162:46-51. doi: 10.1016/j.talanta.2016.09.066. Epub 2016 Oct 4.

DOI:10.1016/j.talanta.2016.09.066

PMID:27837856

Abstract

A novel and simple fluorescent biosensor has been realized through the fluorescence quenching of graphite carbon nitride (g-CN) for mercuric ion (Hg) detection. In this assay, the g-CN sheets which were functionalized with single-stranded DNA (ssDNA) aptamer showed strong fluorescence emission at 440nm under the excitation of 380nm in the absence of Hg. When added to the assay solution, Hg was embedded in the hairpin-shaped double-stranded DNA (dsDNA) due to the formation of the thymine-Hg-thymine (T-Hg-T) complex, which made the Hg close to the surface of g-CN sheet. Therefore, the fluorescence of g-CN was quenched. This sensor has good selectivity with a limit of detection as low as 0.17nM under optimal conditions. The present work demonstrates that the g-CN-based fluorescent sensor has a promising application for detection of metal ions in real samples.

摘要

通过石墨相氮化碳（g-CN）对汞离子（Hg）检测的荧光猝灭，实现了一种新颖而简单的荧光生物传感器。在该测定法中，功能化的 g-CN 片在没有 Hg 的情况下，在 380nm 的激发下于 440nm 处显示出强荧光发射。当加入到测定溶液中时，由于形成胸腺嘧啶-Hg-胸腺嘧啶（T-Hg-T）复合物，Hg 嵌入发夹状双链 DNA（dsDNA）中，这使得 Hg 靠近 g-CN 片的表面。因此，g-CN 的荧光被猝灭。在最佳条件下，该传感器具有良好的选择性，检测限低至 0.17nM。本工作表明，基于 g-CN 的荧光传感器在实际样品中金属离子的检测方面具有广阔的应用前景。