Charge and Current Measuring Electronics for Bio-Medical Applications

The motion of electric charge is involved in several processes such as an electrochemical reaction taking place at a metal/electrolyte interface, the measurement of electrical impedance of a sample between a couple of electrodes or the absorption of a photon in a semiconductor and its conversion into an electron/hole pair (Fig. 1). Consequently, the quantification of the amount of charge collected at a sensing electrode is relevant in a broad variety of applications. This brief tutorial focuses on the challenges and techniques of measuring charge, primarily at the micro-scale, with application in the bio-medical field. © 1998-2012 IEEE.