Proton NMR Relaxation Times of Polyunsaturated Fatty Acids in Chloroform Solutions and Aqueous Micelles

The spin-lattice (T1) and spin-spin (T2) relaxation times of protons on linoleic acid (LA), arachidonic acid (AA), and DHA in CDCl3 solutions and aqueous micelles were measured. Protons at hydrophobic sites on DHA and AA in micelles had a longer T2 than those on LA, whereas little difference was found for proton relaxation times among fatty acids in CDCl3 solutions. DHA molecules in micelles were thus more flexible than LA in micelles.