title: Low-noise amplification of voltage and current fluctuations arising in epithelia.
abstract: Two low-noise differential input amplifiers designed for voltage and current fluctuation measurements in epithelia are described. The first one uses a matched pair of low-noise transistors and is particularly suited for low-frequency current and voltage noise measurements in frog skin and other preparations with impedances below 1 kOmega. The second one is designed around a matched pair of JFETs and can also be used for higher source impedance. Performance is demonstrated with Na(+) current power density spectra obtained from frog skin with the transistor-input stage.
authors.affiliation: Laboratorium voor Fysiologie, Universiteit te Leuven, BelgiumAbteilung fur Membranforschung an Epithelien, Second Department of Physiology, D6650 Homburg, West Germany.
authors.forename: W
authors.initials: W
authors.lastname: Van Driessche
authors.forename: B
authors.initials: B
authors.lastname: Lindemann