基于“G-4联体”适配子探针的电化学发光传感器检测Pb^(2+)  

Electroluminescence Biosensor for Determination of Pb^(2+) Based on G-Quadruplex of Aptamer probe

作　　者：魏小平[1] 杨峰[1,2] 丁璠 李建平[1] 

机构地区：[1]桂林理工大学广西矿冶与环境科学实验中心化学与生物工程学院,桂林541004 [2]武警黄金部队第九支队

出　　处：《分析化学》2014年第7期942-947,共6页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金(Nos.21165007;21375031);广西矿冶与环境科学实验中心项目(No.KH20121YB003)资助~~

摘　　要：在金电极表面,通过Au-S键接上具有"茎-环"结构的发夹适配子探针(Hairpin aptamer probe,HAP);当加入Pb2+时,促使发夹结构适配子的"茎-环"结构打开,形成G-4联体,暴露出的3'-NH2与CdS量子点(QDs)结合,导致电化学发光,据此可构建测定Pb2+的量子点电化学发光"Turn on"型传感器。对电化学发光传感器进行了表征。在2.0×10-10~5.0×10-8mol/L范围内,Pb2+浓度与其响应的ECL信号呈线性关系,检出限为3.74×10-11mol/L。传感器有良好的选择性、稳定性及重现性。A ＂turn on＂ model of electrochemiluminescence （ ECL）-Pb2＋ biosensor based on G-quadruplex of aptamer probe was developed by using quantum dots （ QDs） as labels. The ECL-Pb2＋ biosensor was prepared by immobilizing a hairpin aptamer probe with a thiol group at 5 ＇-end and an amino group at 3 ＇-end on gold electrode via an Au-S bond. In the presence of Pb2＋, the G-rich hairpin aptamer probe opened the stem-loop and formed G-quadruplex, which exposed the amino group at 3＇-end and then covalently linked to the carboxyl group on the surface of CdS quantum dots. The fabrication and reaction process of the Pb2＋ biosensor were characterized. The responsive ECL intensity was linearly related to the Pb2＋ concentration in the range of 2. 0×10-10-5. 0×10-8 mol/L, with the detection limit of 3. 74×10-11 mol/L. In addition, the ECL biosensor exhibited high sensitivity, good selectivity, satisfying stability, and repeatability.

关 键 词：适配子 铅Ⅱ离子传感器 电化学发光 量子点 信号增强型 G-4联体 

分 类 号：O657.1[理学—分析化学]