Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10429545 | Biosensors and Bioelectronics | 2011 | 7 Pages |
Abstract
Amino (NH2)-terminated IgE aptamers were covalently attached to carboxyl (COOH)-modified NCD surfaces using carbodiimide chemistry. Electrochemical impedance spectroscopy (EIS) was applied to measure the changes in interfacial electrical properties that arise when the aptamer-functionalized diamond surface was exposed to IgE solutions. During incubation, the formation of aptamer-IgE complexes caused a significant change in the capacitance of the double-layer, in good correspondence with the IgE concentration. The linear dynamic range of IgE detection was from 0.03 μg/mL to 42.8 μg/mL. The detection limit of the aptasensor reached physiologically relevant concentrations (0.03 μg/mL). The NCD-based aptasensor was demonstrated to be highly selective even in the presence of a large excess of IgG. In addition, the aptasensor provided reproducible signals during six regeneration cycles. The impedimetric aptasensor was successfully tested on human serum samples, which opens up the potential of using EIS for direct and label-free detection of IgE levels in blood serum.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Dinh T. Tran, Veronique Vermeeren, Lars Grieten, Sylvia Wenmackers, Patrick Wagner, Jeroen Pollet, Kris P.F. Janssen, Luc Michiels, Jeroen Lammertyn,