title: Effects of unsaturation on 2H-NMR quadrupole splittings and 13C-NMR relaxation in phospholipid bilayers.
abstract: Motional order and motional rates in unsonicated phospholipid bilayers were assessed as a function of unsaturation of the phospholipid. A measurement sensitive to motional order was obtained using 2H-NMR of 18:1, 18:1-phosphatidylcholine labelled at positions 9 and 10 with deuterium and included as a probe in phospholipid bilayers of interest at 10 mole percent. Spin lattice relaxation times from magic angle spinning 13C-NMR spectra of phospholipid dispersions of interest were used as a measure of motional rates. Measurements were made of phospholipid bilayers containing from 0 to 8 double bonds per molecule. No large effect of an increase in unsaturation was noted for the 2H-NMR quadrupole splittings or for the 13C-NMR spin lattice relaxation rate.
mesh_terms: D002247:Carbon Isotopes; D003903:Deuterium; D005231:Fatty Acids, Unsaturated / Q000032:analysis*; D008051:Lipid Bilayers; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008954:Models, Biological; D008968:Molecular Conformation; D010713:Phosphatidylcholines
chemical_list: D002247:Carbon Isotopes; D005231:Fatty Acids, Unsaturated; D008051:Lipid Bilayers; D010713:Phosphatidylcholines; D003903:Deuterium