title: Lateral diffusion of lipids separated from rotational and translational diffusion of a fluid large unilamellar vesicle.
abstract: A new method to separate lateral diffusion of lipids in spherical large unilamellar vesicles from the rotational and the translational diffusion of the vesicle as a whole is proposed. The lateral diffusion coefficient DL is obtained as a time-dependent part of the observed diffusion coefficient in vesicles of 800-nm diameters, by systematically changing the diffusion time interval of the high-field-gradient NMR measurement. Although the lipid is in a confined space, the DL of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine is (1.5±0.6)×10(-11) m(2) s(-1) in the fluid state at 45°C, more than one order of magnitude faster than the rotational and the translational diffusion coefficients of the vesicle by the hydrodynamic continuum model. The method provides a potential for quantifying the lateral diffusion of lipids and proteins in fluid bilayer vesicles as model cell membranes in a natural manner.
authors: Faculty of Pharmaceutical Sciences, Himeji Dokkyo University, 7-2-1, Kamiohno, Himeji 670-8524, Japan. yoshii@ccs.engg.nagoya-u.ac.jp
authors: Noriyuki
authors: N
authors: Yoshii
authors: Tomomi
authors: T
authors: Emoto
authors: Emiko
authors: E
authors: Okamura
mesh_terms: D004058:Diffusion; D008055:Lipids / Q000737:chemistry* / Q000302:isolation & purification; D009682:Magnetic Resonance Spectroscopy; D008962:Models, Theoretical
chemical_list: D008055:Lipids