Impedance spectroscopy and biosensing.

Biosystems Technology, Wildau University of Applied Sciences, Bahnhofstrasse 1, 15745 Wildau, Germany.
Advances in Biochemical Engineering/Biotechnology 02/2008; 109:195-237. DOI: 10.1007/10_2007_081
Source: PubMed

ABSTRACT This chapter introduces the basic terms of impedance and the technique of impedance measurements. Furthermore, an overview of the application of this transduction method for analytical purposes will be given. Examples for combination with enzymes, antibodies, DNA but also for the analysis of living cells will be described. Special attention is devoted to the different electrode design and amplification schemes developed for sensitivity enhancement. Finally, the last two sections will show examples from the label-free determination of DNA and the sensorial detection of autoantibodies involved in celiac disease.

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