Abstract <p>Fundamental barrier properties of biomimetic membranes have to be similar to those of biological membranes. Previously, this was demonstrated on many examples for nitrocellulose ultrafilters impregnated with esters of fatty acids. We also discovered that when the filters were impregnated with fatty acids, transmembrane potential starts spontaneous oscillations at or near the melting point of the fatty acid. This effect was observed even when the membrane separated two acidic aqueous solutions with the same ionic composition and without a concentration gradient. Here we describe current oscillations near the melting point, discuss their mechanisms, possible applications and relations to biological channel oscillations.</p>