title: Association of alkali metal cations with phosphatidylcholine liposomal membrane surface.
abstract: Interactions of alkali metal cations (Li+, Na+, K+, Cs+) with phosphatidylcholine (PC) liposomal membranes were investigated through experimental studies and theoretical considerations. Using a microelectrophoresis technique, charge densities of experimental membrane surfaces were measured as a function of the pH of electrolyte solutions. Equilibria between the PC liposomal membranes and monovalent ions were mathematically analyzed and described quantitatively through a previously proposed theoretical model. Association constants between functional groups of PC and the studied ions were determined and used to define theoretical curves of membrane surface charge density versus pH. Theoretical and experimental data were compared to verify the model. The PC membrane was found to have the highest affinity for lithium ions, among the ions tested.
authors.affiliation: Institute of Chemistry, University of Bialystok, Ciolkowskiego 1K, 15-245, Bialystok, Poland. joannak@uwb.edu.pl.
authors.forename: Joanna
authors.initials: J
authors.lastname: Kotyńska
authors.affiliation: Institute of Chemistry, University of Bialystok, Ciolkowskiego 1K, 15-245, Bialystok, Poland.
authors.forename: Izabela
authors.initials: I
authors.lastname: Dobrzyńska
authors.affiliation: Institute of Chemistry, University of Bialystok, Ciolkowskiego 1K, 15-245, Bialystok, Poland.|Laboratory of Electrochemical Power Sources, Faculty of Chemistry, University of Warsaw, Pasteur St. 1, 02-093, Warsaw, Poland.
authors.forename: Zbigniew A
authors.initials: ZA
authors.lastname: Figaszewski
mesh_terms: D002412:Cations / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008081:Liposomes / Q000737:chemistry*; D008672:Metals, Alkali / Q000737:chemistry*; D008962:Models, Theoretical; D010713:Phosphatidylcholines / Q000737:chemistry*; D055672:Static Electricity
chemical_list: D002412:Cations; D008081:Liposomes; D008672:Metals, Alkali; D010713:Phosphatidylcholines
keywords: Association constants; Liposomes; Monovalent cations; Phosphatidylcholine; Surface charge density