Impedance Spectroscopy for Biosensing: Circuits and Applications

Abstract

Impedance spectroscopy is a powerful and versatile technique to investigate electrically materials and devices. Its compatibility with a liquid environment combined with low cost and reduced, size, with respect to optical techniques, makes impedance measurements one of the most promising transducer mechanisms for lab-on-chip and biochip platforms. This chapter presents the impedance sensing methodology applied to the detection and monitoring of cells or molecules in static and dynamic conditions. The electronic circuits and the signal processing required to perform high-resolution impedance measurements are reported pointing out the advantages of advanced custom solutions. The chapter is concluded by a discussion of the design criteria required for the implementation in CMOS (Complementary Metal Oxide Semiconductor) technology of impedance analyzers suitable for impedance biosensing at micro- and nanoscale.