title: Studies on phosphatidylcholine model membranes. I. Iodine permeability measurement by specific ion electrode.
abstract: An iodide specific ion electrode was used to measure iodide released from egg phosphatidylcholine liposomes after passage through an ion exchange column. The permeation process was shown to be a sum of two separate first order processes. The method permits linear initial rates of iodide release to be determined for the first 5 min of permeation. Iodide permeability in the absence of Tris buffer was found to be a decreasing function of pH. In the presence of Tris, iodide permeability went through a minimum ofrom ph 7.3-8.5. the permeability was found to decrease when cholesterol was incorporated into the liposomes.
mesh_terms: D002784:Cholesterol; D004553:Electric Conductivity; D004566:Electrodes; D006863:Hydrogen-Ion Concentration; D007454:Iodides; D007700:Kinetics; D008081:Liposomes; D008433:Mathematics; D008567:Membranes, Artificial; D008954:Models, Biological; D010539:Permeability; D010713:Phosphatidylcholines; D013997:Time Factors
chemical_list: D007454:Iodides; D008081:Liposomes; D008567:Membranes, Artificial; D010713:Phosphatidylcholines; D002784:Cholesterol