Electrochemical Impedance Spectroscopy for Characterization of Electrochemical Sensors and Biosensors

Abstract

Electrochemical impedance spectroscopy is becoming increasingly widely used in the field of electrochemical sensors and biosensors, mainly for characterization of the sensor assemblies, but also as a diagnostic and as a quantitative detection method. The advantages of using EIS are outlined, the information that can be obtained from spectra that is useful for sensor development, and the possibilities for quantitative measurements are discussed. Illustrative examples include the characterization of the interfacial region associated with self-assembled monolayers, the use of impedance to deduce electrooxidation kinetics of nucleic acids in the presence of ultrasonic irradiation in order to avoid adsorption, cation-exchange-polymer-coated electrochemical sensors used for the analysis of trace metal ions in environmental samples and redox-mediated electrochemical enzyme biosensors.