期刊
BIOSENSORS & BIOELECTRONICS
卷 26, 期 10, 页码 4018-4023出版社
ELSEVIER ADVANCED TECHNOLOGY
DOI: 10.1016/j.bios.2011.03.022
关键词
Mercury ions; DNA; Evanescent wave; Fiber optic biosensor
类别
资金
- CDM Inc.
- William and Diane Howard
- 863 National High Science and Technology Development Programs of China [2009AA06A417-07]
- Major Projects on Control and Rectification of Water Body Pollution of China [2008ZX07313-007]
- National Natural Science Foundation of China [21077063]
Mercury ions (Hg2+) are a highly toxic and ubiquitous pollutants requiring rapid and sensitive on-site detection methods in the environment and foods. Herein, we report an envanescent wave DNA-based biosensor for rapid and very sensitive Hg2+ detection based on a direct structure-competitive detection mode. In this system, a DNA probe covalently immobilized onto a fiber optic sensor contains a short common oligonucleotide sequences that can hybidize with a fluorescently labeled complementary DNA. The DNA probe also comprises a sequence of T-T mismatch pairs that binds with Hg2+ to form a T-Hg2+-T complex by folding of the DNA segments into a hairpin structure. With a structure-competitive mode, a higher concentration of Hg2+ leads to less fluorescence-labeled cDNA bound to the sensor surface and thus to lower fluorescence signal. The total analysis time for a single sample, including the measurement and surface regeneration, was under 6 min with a Hg2+ detection limit of 2.1 nM. The high specificity of the sensor was demonstrated by evaluating its response to a number of potentially interfering metal ions. The sensor's surface can be regenerated with a 0.5% SDS solution (pH 1.9) over 100 times with no significant deterioration of performance. This platform is potentially applicable to detect other heavy metal ions or small-molecule analytes for which DNA/aptamers can be used as specific sensing probes. (C) 2011 Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据