Voltage-induce capacitance relaxation of lipid bilayer membranes. Effects of membrane composition.
The specific capacity of black lipid membranes of different phospholipids dissolved in n-alkanes was investigated. The hydrocarbon thickness of these membranes, as calculated from the electric capacity with a dielectric constant of 2.1, was in most cases close to 5 nm. It was found that the specific capacity is not constant with time after blackening. It shows a linear time dependence characteristic for each lipid/solvent system. The influence of a transmembrane potential on the capacity of the membranes was measured. It was shown that the extent of the capacity change, obtained 10 s after applying a voltage, was strongly dependent on the lipid composition as well as the solvent content of the membranes. The capacity change of the membranes seems to be caused mainly by a thickness change and not by an area increase of the membranes.
D004553:Electric Conductivity; D005231:Fatty Acids, Unsaturated; D008564:Membrane Potentials; D008567:Membranes, Artificial; D008954:Models, Biological; D010713:Phosphatidylcholines; D010743:Phospholipids; D013329:Structure-Activity Relationship
D005231:Fatty Acids, Unsaturated; D008567:Membranes, Artificial; D010713:Phosphatidylcholines; D010743:Phospholipids