title: α-gel prepared in sodium methyl stearoyl taurate/behenyl alcohol/water system-characterization of structural changes with water concentration.
abstract: In this study, the changes in the structural and physicochemical properties of an α-crystalline phase (often called an "α-gel") were assessed in a sodium methyl stearoyl taurate (SMT)/behenyl alcohol/water system. The α-gels were characterized focusing on the effects of the alcohol/surfactant ratio and water concentration. Water molecules solubilized in the interlayer of the α-crystalline phase resulting in expanded interlayer spacing. Beyond the solubilization limit of 85 %, water molecules were trapped in the matrix of the α-crystalline phase in non-equilibrium (i.e., two phases). Accordingly, different self-diffusion coefficients for the solubilized and trapped water molecules were measured using a Fourier transform pulsed gradient spin echo technique to monitor the ¹H NMR spectra. It was concluded that the two self-diffusion coefficients correspond to the water solubilized in the interlayer, i.e., "slow water," and trapped in the matrix of the α-crystalline phase, i.e., "fast water."
authors.affiliation: Research Center (Shin-yokohama), Shiseido Co. Ltd. kei.watanabe@to.shiseido.co.jp
authors.forename: Kei
authors.initials: K
authors.lastname: Watanabe
authors.forename: Haruhiko
authors.initials: H
authors.lastname: Inoue
authors.forename: Takashi
authors.initials: T
authors.lastname: Teshigawara
authors.forename: Tomoko
authors.initials: T
authors.lastname: Kimura
mesh_terms: D002627:Chemistry, Physical; D003460:Crystallization; D004058:Diffusion; D005233:Fatty Alcohols; D005583:Fourier Analysis; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D012995:Solubility; D013228:Stearates / Q000737:chemistry*; D013654:Taurine / Q000031:analogs & derivatives* / Q000737:chemistry*; D014867:Water / Q000032:analysis
chemical_list: D005233:Fatty Alcohols; D013228:Stearates; D014867:Water; D013654:Taurine; C529236:docosanol