Lipid lateral diffusion in oriented lipid/D2O multilayers by pulsed NMR |
| |
Authors: | An-Li Kuo Chas G. Wade |
| |
Affiliation: | Department of Chemistry, University of Texas, Austin, TX 78712 U.S.A. |
| |
Abstract: | The temperature and hydration dependences of lipid lateral diffusion in model membrane/D2O multilayers of dipalmitoyl (DPL), dilauryl (DLL) and egg yolk (EYPC) lecithins were measured using pulsed gradient proton nuclear magnetic resonance (NMR) spin echo techniques. Oriented samples were used to minimize anisotropic dipolar interactions and permit formation of a spin echo. Significantly lipid lateral diffusion is hydration dependent over the range studied (15–40% D2O w/w), varying in DPL over this range for example by a factor of 2. For the saturated lipids at the same hydration and temperature, diffusion decreases monotonically as the chain length increases. The results tend to be larger, by factors of 2–5, than the earlier electron spin resonance (ESR) spin label results, the differences being attributable in part to the differences in hydration and to the absence of probe effects in this work. The addition of cholesterol (28.6 mol%) decreases diffusion of the lipids. Comparisons with other methods of lateral diffusion measurements are made. |
| |
Keywords: | DMPA DMPC proton nuclear magnetic resonance phosphorus nuclear magnetic resonance spin-lattice relaxation time TLC thin layer chromatography |
本文献已被 ScienceDirect 等数据库收录! |
|