title: A temperature study of diacetylenic phosphatidylcholine vesicles.
abstract: Dispersions of the diacetylenic phosphatidylcholine, 1,2-bis(10,12-tricosadiynoyl)-sn-glycero-3-phosphocholine, DC8,9PC, undergo a change from vesicles to hollow tubes on cooling. We report here a light scattering and multinuclear NMR study of the lipid vesicles over the temperature range 0-50 degrees C. The 'splitting' of the N+(CH3)3 resonance increases with decreasing temperature, consistent with the light scattering measurements which show a decrease in vesicle size with decreasing temperature. The NMR spectrum remains well-resolved over this temperature range, even at temperatures as low as 3 degrees C. Phosphorus NMR also indicates that the 'bilayer structure' is maintained over this temperature range. The various proton resonances and the phosphorous signal from the lipid vesicles broaden as the temperature is lowered. These results will be helpful in developing a model for the tubule-forming ability of DC8,9PC.
authors.affiliation: Department of Radiation Oncology, East Carolina University School of Medicine, Greenville, NC 27858.
authors.forename: G L
authors.initials: GL
authors.lastname: Jendrasiak
authors.forename: A A
authors.initials: AA
authors.lastname: Ribeiro
authors.forename: M A
authors.initials: MA
authors.lastname: Nagumo
authors.forename: P E
authors.initials: PE
authors.lastname: Schoen
mesh_terms: D000480:Alkynes / Q000737:chemistry*; D053280:Diynes; D008081:Liposomes / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D010316:Particle Size; D010713:Phosphatidylcholines / Q000737:chemistry*; D012542:Scattering, Radiation; D013696:Temperature
chemical_list: D000480:Alkynes; D053280:Diynes; D008081:Liposomes; D010713:Phosphatidylcholines; C053923:1,2-bis(10,12-tricosadiynoyl)phosphatidylcholine