title: A novel oriented system made of fatty acid hexagonal phases with tuneable orientation.
abstract: There is a strong demand in the field of solid state NMR for oriented lipid supramolecular assemblies. This is mainly devoted to biophysical structural studies or materials chemistry because the NMR signal depends on the orientation. Here we report a novel system made of a fatty acid hexagonal phase which self orient in the magnetic field. The orientation occurs within the magnetic field upon cooling the system from its isotropic phase. The cylinders of the hexagonal phase are then oriented parallel to the field. We take advantage that the hexagonal phase is a gel, i.e., the orientation is maintained fixed within the sample tube to investigate the orientational dependence of the deuterium solid state NMR signal using deuterated fatty acids and D(2)O by manually rotating the sample tube within the coil probe. As expected, the oriented signal follows the low |3cos(2)theta-1| where theta is the angle between the long cylindrical axis and the field. We expect this system to be of interest in materials chemistry and structural biology.
authors.affiliation: UR 1268, Biopolymères Interactions Assemblages INRA, équipe ISD, Rue de la Géraudière, 44316 Nantes, France. jean-paul.douliez@nantes.inra.fr
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Douliez
mesh_terms: D003903:Deuterium; D017666:Deuterium Oxide / Q000737:chemistry; D004574:Electromagnetic Fields; D005227:Fatty Acids / Q000737:chemistry*; D007202:Indicators and Reagents; D007553:Isotope Labeling; D008055:Lipids / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008859:Microscopy, Polarization; D008968:Molecular Conformation; D010169:Palmitic Acids / Q000737:chemistry; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D012542:Scattering, Radiation; D014965:X-Rays
chemical_list: D005227:Fatty Acids; D007202:Indicators and Reagents; D008055:Lipids; D010169:Palmitic Acids; D000644:Quaternary Ammonium Compounds; D003903:Deuterium; C009405:tetrabutylammonium; D017666:Deuterium Oxide