一种基于汞特异性DNA和SYBR GREEN I荧光检测Hg^(2+)方法的建立  

Highly Sensitive and Selective Detection of Hg^(2+) in Aqueous Solution with Mercury-specific DNA and SYBR GREEN I

作　　者：吴继魁[1] 卫碧文[2] 林莉[2] 毛芳[1] 周冬香[1] 熊振海[1] 

机构地区：[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

出　　处：《生物技术通报》2013年第4期221-224,共4页Biotechnology Bulletin

基　　金：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)

摘　　要：以富含胸腺嘧啶(thymine)的Hg^(2+)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Hg^(2+)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Hg^(2+)通过T-Hg^(2+)-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Hg^(2+)浓度在0-100 nmol/L范围呈线性,检测限为2nmol/L(S/N=3),而其他金属离子也不会对Hg^(2+)检测造成干扰。该方法简单快速,有望应用于水体中Hg^(2+)的检测。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 1, was reported in the present work. This Hg2＋ specific sensor system composed of two label- free DNA probes with five T-T mis-matches, which could form stable DNA duplexes by thymme-Hg -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 intoDNA duplexes. By momtormg Hg -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 issimple and rapid, which can be used to momtor the Hg concentration in drinking water.

关 键 词：HG^2+ DNA探针 荧光检测 SYBR GREEN I 

分 类 号：R114[医药卫生—卫生毒理学]