Journal
TALANTA
Volume 78, Issue 4-5, Pages 1240-1245Publisher
ELSEVIER
DOI: 10.1016/j.talanta.2009.01.034
Keywords
Aptamer; Thrombin; Polyamidoamine dendrimer; Electrochemical impedance spectroscopy
Categories
Funding
- National Natural Science Foundation of China [90713022]
- National Key Basic Research Development Project of China [2007CB714500]
- Chinese Academy of Sciences [KJCX2-YW-H11]
Ask authors/readers for more resources
A label-free and highly sensitive impedimetric aptasensor based on a polyamidoamine dendrimer modified gold electrode was developed for the determination of thrombin. Amino-terminated polyamidoamine dendrimer was firstly covalently attached to the cysteine functionalized gold electrode through glutaraldehyde coupling. Subsequently, the dendrimer was activated with glutaraldehyde, and amino-modified thrombin aptamer probe was immobilized onto the activated dendrimer monolayer film. The layer-by-layer assembly process was traced by surface plasmon resonance and electrochemical impedance spectroscopy. After electrode preparation, the detection of thrombin was investigated in the presence of the reversible [Fe(CN)(6)](3-)/(4-) redox couple using impedance technique. The results showed that the charge-transfer resistance (R-ct) value had a linear relationship with the concentrations of thrombin in the range of 1-50 nM, and the detection limit (S/N = 3) as low as 0.01 nM was obtained. The covalent immobilization of dendrimer on the electrode surface not only improved the immobilization capacity of probe molecules but also magnified the response signal. The aptasensor exhibited favorable regeneration ability, selectivity and stability. it also showed the detectability in biological fluid. (C) 2009 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available