Electroluminescence Biosensor for Determination of Pb2+Based on G-Quadruplex of Aptamer probe
10.11895/j.issn.0253-3820.140197
- VernacularTitle:基于“G-4联体”适配子探针的电化学发光传感器检测Pb2+
- Author:
Xiaoping WEI
;
Feng YANG
;
Fan DING
;
Jianping LI
- Publication Type:Journal Article
- Keywords:
"Aptamer;
Lead ion Ⅱ sensor;
Electrochemiluminescence;
Quantum dots;
""Turn on"" model;
G-quadruplex"
- From:
Chinese Journal of Analytical Chemistry
2014;(7):942-947
- CountryChina
- Language:Chinese
-
Abstract:
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.
