Jump to main content
Jump to site search
PLANNED MAINTENANCE Close the message box

Scheduled maintenance upgrade on Thursday 4th of May 2017 from 8.00am to 9.00am (BST).

During this time our websites will be offline temporarily. If you have any questions please use the feedback button on this page. We apologise for any inconvenience this might cause and thank you for your patience.


Issue 43, 2016
Previous Article Next Article

A photoelectrochemical DNA sensor for the detection of Hg2+ based on Hg2+-mediated oligonucleotide switching

Author affiliations

Abstract

A sensitive photoelectrochemical (PEC) method for Hg2+ detection is reported, based on the Hg2+-mediated structural switch of an oligonucleotide strand and biocatalytic precipitation (BCP) on a CdS quantum dot electrode. The principle is that, in the absence of Hg2+, the oligonucleotide strand forms a stem-loop, thus a G-rich sequence in the strand is partially caged in the stem-loop structure and cannot fold into a G-quadruplex. While in the presence of Hg2+, the T–Hg2+–T coordination leads to the formation of another stem-loop structure and allows the G-rich sequence to fold properly and bind hemin to form a stable G-quadruplex/hemin complex, which could accelerate oxidation of 4-chloro-1-naphthol (4-CN) by H2O2 to yield the insoluble (BCP reaction) and insulating product benzo-4-chlorohexadienone on the photoelectrode, thereby efficiently causing the change in the photocurrent signal. This simple PEC sensor could detect aqueous Hg2+ at concentrations as low as 4 nM with high selectivity.

Graphical abstract: A photoelectrochemical DNA sensor for the detection of Hg2+ based on Hg2+-mediated oligonucleotide switching

Back to tab navigation
Please wait while Download options loads

Publication details

The article was received on 06 Aug 2016, accepted on 30 Sep 2016 and first published on 03 Oct 2016


Article type: Paper
DOI: 10.1039/C6AY02222G
Citation: Anal. Methods, 2016,8, 7762-7766
  •   Request permissions

    A photoelectrochemical DNA sensor for the detection of Hg2+ based on Hg2+-mediated oligonucleotide switching

    W. Zhang, B. Shan, D. Liang, Y. Shi, D. Han and C. Huang, Anal. Methods, 2016, 8, 7762
    DOI: 10.1039/C6AY02222G

Search articles by author