title: The effect of pH on the electrical capacitance of phosphatidylcholine-phosphatidylserine system in bilayer lipid membrane.
abstract: This paper reports measurements on the pH dependence of the electrical capacitance of lipid membranes formed by 1:1 phosphatidylcholine-phosphatidylserine mixtures. A theoretical model was developed to describe this dependence, in which the contributions of functional groups (as the active centers of adsorption of the hydrogen and hydroxide ions) to the overall membrane capacitance were assumed to be additive. The proposed model was verified experimentally using electrochemical impedance spectroscopy. The theoretical predictions agreed with the experimental results over the measured pH range. A minimum corresponding to the isoelectric point appeared in both the theoretical equation and the experimental data.
authors.affiliation: Institute of Chemistry, University of Bialystok, Al. J. Pilsudskiego 11/4, 15-443, Bialystok, Poland, monikan@uwb.edu.pl.
authors.forename: Monika
authors.initials: M
authors.lastname: Naumowicz
authors.forename: Zbigniew Artur
authors.initials: ZA
authors.lastname: Figaszewski
mesh_terms: D003198:Computer Simulation; D025802:Electric Capacitance; D006863:Hydrogen-Ion Concentration; D007526:Isoelectric Point; D008051:Lipid Bilayers / Q000737:chemistry*; D008956:Models, Chemical; D010713:Phosphatidylcholines / Q000737:chemistry*; D010718:Phosphatidylserines / Q000737:chemistry*
chemical_list: D008051:Lipid Bilayers; D010713:Phosphatidylcholines; D010718:Phosphatidylserines