Direct Demonstration of Dielectric Breakdown in the Membranes of Valonia utricularis

Abstract

Abstract It is shown that if the membrane potential of cells of Valonia utricularis was increased rapidly by applying ~500 μs current pulses, dielectric breakdown of the membrane occured when the potential reached a value of ~0.85 V. The breakdown phenomenon observed was not associated with global damage to the cell or its membrane. The process could be repeated after a short resealing time (~ 10s), many times on a single cell. The rapidity of the breakdown process (~1 μs) rules out the possibility that dielectric breakdown occurs by a mechanism similar to that of punch-through, which involves changes in ionic profiles.