Ion-channellike behavior in lipid bilayer membranes at the melting transition, Submitted

It is well known that at the gel-liquid phase transition temperature a lipid bilayer membrane exhibits an increased ion permeability. We analyze the quantized currents in which the increased permeability presents itself. The open time histogram shows a “-3/2 ” power law which implies an open-closed transition rate that decreases like k(t) ∝ t−1 as time evolves. We propose a “pore freezing ” model to explain the observations. We discuss how this model also leads to the 1/fα noise that is commonly observed in currents across biological and artificial membranes. PACS numbers: 05.70.Fh, 87.10.Mn, 87.16.dp I