Highly sensitive fluorescent sensor for mercury ion based on photoinduced charge transfer between fluorophore and π-stacked T-Hg(II)-T base pairs
Highly sensitive fluorescent sensor for mercury ion based on photoinduced charge transfer between fluorophore and π-stacked T-Hg(II)-T base pairs
复制标题
DOI：
10.1016/j.talanta.2009.05.001
复制
发表时间：
2009-08-15
期刊：
影响因子：
6.1
通讯作者：
Chen, Guonan
中科院分区：
文献类型：
--
作者：
Guo, Liangqia;Hu, Hong;Chen, Guonan
报道了一种新颖、简单的单荧光标记寡核苷酸汞离子传感器。以荧光素标记寡核苷酸多聚(DT)为供体。基于Hg(II)与T-T错配碱基对的特异性结合，在Hg(II)离子的加入上形成具有“三明治”结构的pi-堆积的[T-Hg(II)-T]，促进了通过光诱导电荷转移(PCT)的电子转移，从而为被激发的荧光团创造了一个额外的非辐射衰变通道，并触发了荧光被猝灭。Pi堆积的[T-Hg(II)-T]不仅可以识别汞离子，还可以作为电子受体猝灭给电子体。汞离子的线性范围为0-1.0微米，检出限为20毫微米。详细研究了该体系的荧光猝灭现象、猝灭机理、可靠性和选择性。(C)2009爱思唯尔B.V.保留所有权利。
A novel and simple oligodeoxyribonucleotide-based sensor with single fluorophore-labeled for mercury ion sensing was reported. An oligodeoxyribonucleotide poly(dT) was labeled with fluorescein as donor. Based on the specific binding of Hg(II) to T-T mismatch base pairs, the formation of pi-stacked [T-Hg(II)-T] with "sandwich" structure on the addition of Hg(II) ions facilitates the electron transfer via photoinduced charge transfer (PCT), which creates an additional nonradiative decay channel for excited fluorophore and triggers the fluorescence to be quenched. The pi-stacked [T-Hg(II)-T] functioned not only as mercury ion recognition but also as an electron acceptor to quench the donor. A linear relationship was observed over the range of 0-1.0 mu M with the detection limit of 20 nM for mercury ions. The fluorescence quenching phenomenon and quenching mechanism, reliability and selectivity of the system were investigated in detail. (C) 2009 Elsevier B.V. All rights reserved.