Nonlinear conduction in bilayer lipid membranes - effect of temperature

We present here our investigation on the effect of temperature on the reversible nonlinearity as manifested in the DC I-V characteristic of bilayer lipid membrane (BLM). V-c and I-c the values of voltage and current at the onset of nonlinearity, have been found to be functions of temperature, and the nonlinearity has been found to decrease with increase in temperature. By proper scaling of voltage and current by V-c and I-c, respectively, the I-V curves taken at different temperatures collapse into one single curve, showing the universality in their nature. A log-log plot of I-c vs, sigma (0) (linear conductance) is a straight line where I-c scales with sigma (0) as I-c similar to sigma (1.56)(0). A possible mode of charge conduction in BLM, which is a disordered composite system of lipid and water molecules, has been proposed on the basis of these experimental results. (C) 2001 Elsevier Science B.V. All rights reserved.