Impedimetric aptasensors using nanomaterials

This chapter describes aptamer biosensors that employ electrochemical impedance signal as transduction principle. With this idea, detection of substances other than nucleic acids through specific conformer folding region interacting with a complementary substance is the starting point to develop these affinity sensors. Substances detected can be ions, small organic molecules, proteins, even microorganisms, or cells. Electrochemical impedance spectroscopy permits, then, a labeless detection, by simple use of a redox probe. As current topic, it will focus on the use of nanocomponents to improve sensor performance, mainly carbon nanotubes integrated in the sensor platform, graphene or nanoparticles, for signal amplification. Different formats and variants available for analytical applications will be reviewed. © 2018 Elsevier Inc. All rights reserved.