A simple assay to amplify the electrochemical signal by the aptamer based biosensor modified with CdS hollow nanospheres |
| |
Authors: | Li Yanfen Bao Jianchun Han Min Dai Zhihui Wang Huaisheng |
| |
Institution: | Jiangsu Key Laboratory of Biofunctional Materials, Laboratory of Electrochemistry, College of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210097, PR China. |
| |
Abstract: | A simple method to amplify the electrochemical signal by an aptamer with 22 bases modified with CdS hollow nanospheres (CdSHNs) was described. Using the thrombin as a model, the interaction between the aptamer and CdSHNs was characterized by cyclic voltammetry, electrochemical impedance spectroscopy and circular dichroism spectroscopy. CdSHNs promoted the electron transfer between the gold electrode and K(3)Fe(CN)(6)] and facilitated the conformation conversion of the aptamer from hairpin to G-quadruplex after the aptamer interacted with thrombin. Under optimal conditions, the modified electrode could be used for the determination of thrombin from 0 to 33 μg mL(-1) and the sensitivity was 1.34 μA mL μg(-1)cm(-2), while the linear range of the modified electrode without the immobilization of CdSHNs was from 2.75 to 27.5 μg mL(-1) and the sensitivity was 0.062 μA mL μg(-1)cm(-2). This constructed biosensor also had a good stability, specificity, reproducibility and accuracy which could provide a promising platform for fabrication of aptamer based biosensors. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|