基于荧光素标记的DNA-Cu(Ⅱ)络合物的荧光增强型氰根离子传感器  

A New Fluorescence Turn-on Cyanide Sensor with Fluorescein-labeled Oligo DNA-Cu(Ⅱ) Ensemble

作　　者：黄显虹[1] 张关心[1] 张德清[1] 

机构地区：[1]中国科学院化学研究所有机固体实验室,北京100190

出　　处：《化学学报》2012年第20期2133-2136,共4页Acta Chimica Sinica

基　　金：国家自然科学基金(Nos.21021091,21075126);科技部973计划项目(No.2011CB808400);电子科技大学电子薄膜与集成器件国家重点实验室开放基金(No.KFJJ201010)资助~~

摘　　要：利用铜离子与荧光素标记的寡核苷酸链、氰根离子结合能力的差异,发展了一种水相中氰根离子检测的新方法.研究表明,该检测方法可以较灵敏地检测水相中的氰根离子,其检测下限达到0.02μmol/L,且具有较好的选择性和潜在的实际应用价值.In this paper, a new fluorescence turn-on sensor for cyanide in aqueous solution was established with fluo- rescein-labeled oligo DNA. The design rationale is explained as follows： （1） Fluorescein-labeled oligoDNA （FAM-DNA） shows strong fluorescence in aqueous solution. But, it is expected that the fluorescence of FAM-DNA will be quenched be- cause of the formation of stable complex of FAM-DNA with Cu^2＋; （2） Demetallation from the complex of FAM-DNA with Cu^2＋ because of the reaction of CN and Cu^2＋ and formation Cu（CN）2 ; as a result the fluorescence of FAM-DNA emerges again. Therefore, it is anticipated that the fluorescence of the ensemble of FAM-DNA and Cu^2＋ increases by in- creasing the concentration ofCN . Thus, the ensemble of FAM-DNA and Cu^2＋ can be utilized for the detection ofCN . The results revealed that the fluorescence of FAM-DNA were quenched efficiently in the presence of Cu^2＋ （1.35 μmol/L） due to the intramolecular photoinduced electron transfer within the ensemble of FAM-DNA and Cu^2＋. Other metal ions, such as K^＋, Ca^2＋, Ba^2＋, Mg^2＋, Fe^3＋, Hg^2＋, Ni^2＋, Pb^2＋, Zn^2＋ and Ag^＋, induced negligible fluorescence quenching for FAM-DNA under the same conditions. However, fluorescence of the system increased gradually by increasing the concentration of CN-in the ensemble solution, and the fluorescence intensity varies almost linearly vs. the concentration of CN . The detection limit of CN- with the ensemble of FAM-DNA and Cu^2＋ was estimated to be 0.02 μmol/L, which is much lower than the maximum level （1.9 μmol/L） of CN- in drinking water permitted by the World Health Organization （WHO）. Moreover, the response of the ensemble of FAM-DNA and Cu^2＋ to solutions containing CN- （40 μmol/L） in the presence of relevant ionic species, including F^-, CI^-, Br^-, I^-, NO3^-, HSO4^-,CO3^2-, CH3COO^-, H2PO4^-, SCN^-, and N3^- （at a concentration level over 10 times higher to that of CN-）, was investigated. The results indicate

关 键 词：氰根离子 寡核苷酸 铜离子 荧光传感器 

分 类 号：TP212.2[自动化与计算机技术—检测技术与自动化装置]