title: Interfacial tension of phosphatidylcholine-phosphatidylserine system in bilayer lipid membrane.
abstract: The effect of pH of electrolyte solution on the interfacial tension of lipid membrane formed of phosphatidylcholine (PC, lecithin)-phosphatidylserine (PS) system was studied. In this article, three models describing the H+ and OH- ions adsorption in the bilayer lipid surface are presented. In Model I and Model II, the surface is continuous with uniformly distributed functional groups constituting the centres of H+ and OH- ions adsorption while in the other the surface is built of lipid molecules, free or with attached H+ and OH- ions. In these models contribution of the individual lipid molecule forms to interfacial tension of the bilayer were assumed to be additive. In Model III the adsorption of the H+ and OH- ions at the PC-PS bilayer surface was described in terms of the Gibbs isotherm. Theoretical equations are derived to describe this dependence in the whole pH range.
authors.affiliation: Institute of Chemistry, University of Bialystok, Al. J. Pilsudskiego 11/4, 15-443 Bialystok, Poland.
authors.forename: Aneta D
authors.initials: AD
authors.lastname: Petelska
authors.forename: Zbigniew A
authors.initials: ZA
authors.lastname: Figaszewski
mesh_terms: D000327:Adsorption; D002462:Cell Membrane / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008051:Lipid Bilayers / Q000737:chemistry*; D008956:Models, Chemical; D010713:Phosphatidylcholines / Q000737:chemistry*; D010718:Phosphatidylserines / Q000737:chemistry*; D013500:Surface Tension; D013816:Thermodynamics
chemical_list: D008051:Lipid Bilayers; D010713:Phosphatidylcholines; D010718:Phosphatidylserines