Journal Article

Rapid on-site/in-situ detection of heavy metal ions in environmental water using a structure-switching DNA optical biosensor

Zhu, Anna, Shi, Hanchang, Liu, Jingquan, Long, Feng, Wang, Hongchen

2013

Overview

A structure-switching DNA optical biosensor for rapid on-site /in situ detection of heavy metal ions is reported. Mercury ions (Hg 2+ ), highly toxic and ubiquitous pollutants, were selected as model target. In this system, fluorescence-labeled DNA containing T-T mismatch structure was introduced to bind with DNA probes immobilized onto the sensor surface. In the presence of Hg 2+ , some of the fluorescence-labeled DNAs bind with Hg 2+ to form T-Hg 2+ -T complexes through the folding of themselves into a hairpin structure and dehybridization from the sensor surface, which leads to decrease in fluorescence signal. The total analysis time for a single sample was less than 10 min with detection limit of 1.2 nM. The rapid on-site/ in situ determination of Hg 2+ was readily performed in natural water. This sensing strategy can be extended in principle to other metal ions by substituting the T-Hg 2+ -T complexes with other specificity structures that selectively bind to other analytes.

• Publisher: Nature Publishing Group UK,Nature Publishing Group
• Subject: 631/45/147 / 639/624/1107/510 / 704/172/169/895 / 704/172/169/896 / Biosensing Techniques - instrumentation / Biosensing Techniques - methods / Biosensors / Deoxyribonucleic acid / DNA / DNA - chemistry / DNA probes / DNA structure / Environmental Monitoring / Fluorescence / Heavy metals / Humanities and Social Sciences / Humans / Ions / Ions - analysis / Ions - chemistry / Mercury / Metal ions / Metals, Heavy - analysis / Metals, Heavy - chemistry / multidisciplinary / Onsite / Pollutants / Reproducibility of Results / Science / Sensitivity and Specificity / Water - analysis / Water - chemistry / Water Quality - standards