生物技术通报 ›› 2013, Vol. 0 ›› Issue (4): 221-224.

• 论文 • 上一篇    下一篇

一种基于汞特异性DNA 和SYBR GREEN I 荧光检测Hg2+方法的建立

吴继魁1, 卫碧文2, 林莉2, 毛芳1, 周冬香1, 熊振海1   

  1. 1. 上海海洋大学食品学院,上海 201306 ;2. 上海出入境检验检疫局,上海 200135
  • 收稿日期:2013-02-17 修回日期:2013-04-22 出版日期:2013-04-22 发布日期:2013-04-22
  • 作者简介:吴继魁,博士,讲师,研究方向:生物传感器;E-mail :jkwu@shou.edu.cn
  • 基金资助:

    上海海洋大学博士启动基金项目(A-2400-10-0129),上海自然科学基金项目(11ZR1415400)

Highly Sensitive and Selective Detection of Hg2+ in Aqueous Solution with Mercury-specific DNA and SYBR GREEN I

Wu Jikui1, Wei Biwen2, Lin Li2, Mao Fang1, Zhou Dongxiang1, Xiong Zhenhai1   

  1. 1. College of Food Science and Technology,Shanghai Ocean University,Shanghai 201306 ;2. Shanghai Entry-Exit Inspection and Quarantine Bureau,Shanghai 200135
  • Received:2013-02-17 Revised:2013-04-22 Published:2013-04-22 Online:2013-04-22

摘要:

以富含胸腺嘧啶(thymine)的Hg2+ 特异性DNA 为识别元件,利用SYBR GREEN I 分子光“开关”的特性,建立 了一种高灵敏、高选择性荧光均相检测Hg2+ 的新方法。该检测体系由两条非标记、含有5 个thymine-thymine(T-T)错配碱基对的 DNA 探针组成。T-T 错配使两条DNA 探针以单链形式存在于溶液中,而 Hg2+ 通过T-Hg2+-T 配位作用可以与两条DNA 探针结合并 形成稳定的双链结构。在优化条件下,荧光强度与Hg2+ 浓度在0-100 nmol/L 范围呈线性,检测限为2 nmol/L(S/N=3),而其他金 属离子也不会对Hg2+ 检测造成干扰。该方法简单快速,有望应用于水体中Hg2+ 的检测。

关键词: Hg2+, DNA, 探针, 荧光检测, SYBR, GREEN I

Abstract:

A novel “signal-on” assay for sensitive and selective detection of Hg2+ in aqueous solution based on mercury-specific DNA and a molecular light switch complex, SYBR GREEN I, was reported in the present work. This Hg2+ specific sensor system composed of two labelfree DNA probes with five T-T mis-matches, which could form stable DNA duplexes by thymine-Hg2+-thymine(T-Hg2+-T)in the presence of Hg2+. The fluorescence of SYBR GREEN I is weak in aqueous solution, and significant fluorescence can be observed when intercalating into DNA duplexes. By monitoring Hg2+-dependent fluorescence intensity enhancement, highly sensitive and selective determination of Hg2+ has been achieved. Under the optimum conditions, the fluorescence intensity was proportional to the concentration of Hg2+ in the range of 5-100 nmol/L. A detection limit of 2 nmol/L Hg2+ was achieved. The presence of other metal ions did not interfere with the detection of Hg2+. This approach is simple and rapid, which can be used to monitor the Hg2+ concentration in drinking water.

Key words: Hg2+, DNA probe, Fluorimetry, SYBR GREEN I