Electrochemical Genosensors

© 2015 John Wiley & Sons, Ltd. All rights reserved. DNA biosensors, also called genosensors, are devices that are based on the immobilization of a single-stranded (ss) oligonucleotide probe onto a transducer surface that recognize-by hybridization-its complementary target sequence. In the case of electrochemical genosensors, the binding of the surface-confined probe and its complementary target strand is translated into a useful electrical signal. Electrochemical genosensors have advantages such as the use in many cases of simple, small, and portable equipment easy to be operated even by nonprofessional users. Besides the possibility to be miniaturized, these devices are usually of a low cost offering at the same time measurements with high sensitivity and specificity. In this chapter, a general description of DNA and nanomaterial-based detection systems is given. Several detection methods based, for example, on label-free formats and utilizing electrochemical and/or surface electroactivity of various platforms or direct methods relaying on the intrinsic electrochemical properties of DNA (the oxidation of purine bases, particularly guanine) are also given for applications in various fields including overall food quality and security. Copyright