量子点-钌配合物二元体系：通过双色荧光检测识别双链DNA。

Quantum dot-ruthenium complex dyads: recognition of double-strand DNA through dual-color fluorescence detection.

作者信息

Zhao Dan, Chan W H, He Zhike, Qiu Ting

机构信息

Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, PR China.

出版信息

Anal Chem. 2009 May 1;81(9):3537-43. doi: 10.1021/ac9000892.

DOI:10.1021/ac9000892

PMID:19351144

Abstract

We have developed a new fluorescent ensemble probe comprising an ionic conjugate between water-soluble thioglycolic acid (TGA) capped CdTe quantum dots (QDs) and Ru(bpy)(2)(dppx)(2+) for the dual-color detection of complementary double-stranded DNAs (dsDNA). To provide the platform for DNA detection, the Ru-complex was first employed as an effective fluorescence quencher to TGA capped QDs via photoinduced electron transfer process. Because of its strong binding affinity with Ru(bpy)(2)(dppx)(2+), complementary dsDNA can break up the low fluoresced ionic ensemble, set free the luminescent QDs, and concomitantly generate the Ru(bpy)(2)(dppx)(2+) intercalated DNA complex. Thus, the recognition of dsDNA by Ru(bpy)(2)(dppx)(2+) can be realized via both the restoration of QDs fluorescence and the emergence of a new fluorescence emission signal of the quencher-substrate at 609 nm, while single-stranded DNA, ribonucleic acid, bovine albumin serum, and biological relevant metal ions cannot produce the similar results. Therefore, a simple, fast, sensitive, and highly selective assay for dsDNA has been realized.

摘要

我们开发了一种新型荧光组合探针，它由水溶性巯基乙酸（TGA）包覆的碲化镉量子点（QDs）与Ru(bpy)(2)(dppx)(2+)之间的离子共轭物组成，用于互补双链DNA（dsDNA）的双色检测。为了提供DNA检测平台，首先通过光诱导电子转移过程，将Ru配合物用作TGA包覆量子点的有效荧光猝灭剂。由于其与Ru(bpy)(2)(dppx)(2+)具有很强的结合亲和力，互补双链DNA可以破坏低荧光的离子组合，释放出发光的量子点，并同时生成Ru(bpy)(2)(dppx)(2+)插入的DNA复合物。因此，Ru(bpy)(2)(dppx)(2+)对双链DNA的识别可以通过量子点荧光的恢复以及猝灭剂-底物在609nm处新荧光发射信号的出现来实现，而单链DNA、核糖核酸、牛血清白蛋白和生物相关金属离子则不会产生类似结果。因此，实现了一种简单、快速、灵敏且高度选择性的双链DNA检测方法。