Temperature- and Applied Voltage-Dependency of Valinomycin-Mediated Ion Transport across Planar Lipid Bilayer Membrane by Voltage Jump Method

Abstract

An improved voltage jump method characterized by a higher time resolution (0.2 μsec) as well as a larger dynamic range (80 dB) than the conventional method is developed to measure electric current relaxation accurately. by this method the rate constants in the valinomycin-mediated transport of potassium ions through an azolectin bilayer membrane are determined from the current relaxation curve. From an investigation of the influence of applied voltage and temperature on each rate constant, a potential energy profile and a displacement of the potential energy profile depending on applied voltage are estimated.