Proton NMR studies of the interaction of water with lecithin in non-polar organic media

✍ Scribed by V.V. Kumar; P. Raghunathan

• Publisher: Elsevier Science
• Year: 1986
• Tongue: English
• Weight: 530 KB
• Volume: 41
• Category: Article
• ISSN: 0009-3084
• DOI: 10.1016/0009-3084(86)90007-1

✦ Synopsis

Lecithin-non-polar solvent-water systems are studied by proton NMR spin-lattice (T~) and spin-spin relaxation (T2) times. T~ studies indicate that one water molecule is tightly bound to the polar head group. The rotational correlation time (re) of the water pool is shortened as a function of added water, until r~ finally approaches the value of 3 × 10 ~2 s for normal, bulk water. The microviscosity of the water environment is very high and falls offrapidly as a function of added water. The water added is solubilized in the polar core of the reverse micelle; this increases the motion of the polar head group but has no effect on the hydrocarbon chains. 72 studies of those systems reveal that, in addition to intramolecular dipole relaxation, the observed relaxation processes are possibly strongly influenced by exchange narrowing, spin-rotation and chemical shift anisotropy.