Thrombin Biosensor Based on Rare Earth Ion Mediated Fluorescence Switch of Graphene Quantum Dots
10.11895/j.issn.0253-3820.171293
- VernacularTitle:基于稀土离子介导石墨烯量子点荧光开关的凝血酶生物传感器
- Author:
Tian Tian WEI
1
;
Ping Ru LIANG
;
Ding Jian QIU
Author Information
1. 南昌大学化学学院
- Keywords:
Rare earth ion;
Graphene quantum dots;
Fluorescence switch;
Thrombin;
Sensing
- From:
Chinese Journal of Analytical Chemistry
2017;45(12):1915-1920
- CountryChina
- Language:Chinese
-
Abstract:
A label-free method for sensitive and selective detection of thrombin ( Tb) was constructed based on rare earth ion mediated fluorescence switch of graphene quantum dots ( GQDs) . Rare earth ion ( Er3+) can assemble onto the surface of GQDs through the coordination interaction between Er3+ ions and the carboxylate groups located on the surface or edge of the GQDs, resulting in the aggregation of the GQDs and thereby decrease of the fluorescence of the GQDs. In the presence of Tb, the oxygen and nitrogen-donor atoms in Tb can coordinate with Er3+ ions and compete with the carboxylate groups on GQDs to coordinate Er3+ ions, thus the interaction between GQDs and Er3+ ions is reduced, which lead to the restoration of the GQDs fluorescence. In this study, the sensing mechanism was demonstrated by transmission electron microscopy, atomic force microscope, Fourier transform infrared spectroscopy, UV-Vis absorption and fluorescence spectroscopy. The limit of detection for Tb assay was as low as 0. 049 nmol/L. Moreover, this assay was successfully applied to the selective determination of Tb in real samples.
