Characterization of non-linear electrical behaviour of lipid bilayer of cell membranes

The plasma membrane of a cell serves the vital function of partitioning the molecular contents of the cytoplasm from its external environment. These membranes are largely composed of amphiphilic lipids which self assemble into highly insulating structures and thus present a large energy barrier to transmembrane ionic transport. However, the lipid matrix can be disrupted by a strong external electric field leading to an increase in transmembrane conductivity and diffusive permeability. These effects are the result of formation of aqueous pores in the membrane which also alter the electrical potential across the membrane. The double vaseline gap voltage clamp method was used to measure transmembrane current at different transmembrane potentials. The results show a non-linear dependence of membrane conductance on applied electric field