title: Acyl chain orientational order in the hexagonal HII phase of phospholipid-water dispersions.
abstract: The deuterium nuclear magnetic resonance (2H NMR) spectrum of perdeuterated tetradecanol in a mixture of 1-palmitoyl-2-oleoyl-phosphatidylethanolamine (POPE) and water was used to compare the variation of the acyl chain orientational order parameter, S(n), with carbon position, n, in the liquid crystalline lamellar (L alpha) and hexagonal (HII) phases. The characteristics independence of S(n) with n (plateau) normally observed in the L alpha phase is replaced by a more rapid decrease of S(n) with n in the HII phase. It is suggested that as a consequence of the geometrical characteristics of the HII phase, there is an increase in conformational freedom available to different parts of the acyl chain.
authors.affiliation: Department of Physics, University of British Columbia.
authors.forename: E
authors.initials: E
authors.lastname: Sternin
authors.forename: B
authors.initials: B
authors.lastname: Fine
authors.forename: M
authors.initials: M
authors.lastname: Bloom
authors.forename: C P
authors.initials: CP
authors.lastname: Tilcock
authors.forename: K F
authors.initials: KF
authors.lastname: Wong
authors.forename: P R
authors.initials: PR
authors.lastname: Cullis
mesh_terms: D008051:Lipid Bilayers; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008954:Models, Biological; D008968:Molecular Conformation; D010714:Phosphatidylethanolamines; D014867:Water
chemical_list: D008051:Lipid Bilayers; D010714:Phosphatidylethanolamines; D014867:Water; C057561:1-palmitoyl-2-oleoylphosphatidylethanolamine