The effect of amphiphilic counterions on the gel-fluid phase transition of the lipid bilayer

Abstract

Monte Carlo simulation based on the ten-state Pink's model has been applied to study the effect of amphiphilic counterions on the gel-fluid phase transition of lipid bilayers. Based on the theoretical results obtained, one can explain the lack of measurable effect of alkylsulphonate on lipid membrane permeability. An anionic compound with long alkyl chain when applied to a membrane modified with a cationic compound of the same chain length can cancel the effect of the latter due to the formation of an ionic pair that resembles the lipid molecules that form the membrane. The results obtained were compared with experimental results and proved helpful in giving them a more satisfactory interpretation.