title: Biocompatible lecithin organogels: structure and phase equilibria.
abstract: The microstructure of organogels formed upon the addition of tiny amounts of water to a solution of lecithin in fatty acid esters (viz. isopropylpalmitate and ethyloleate) was investigated by means of molecular self-diffusion measurements. In both systems lecithin and water form disconnected cylindrical reverse micelles. The ternary phase map for the lecithin/water/isopropylpalmitate has been investigated in detail. The organogel exists in a narrow region close to the lecithin-oil binary axis; for higher water content equilibrium between lamellae and reverse micelles is found. Lamellar phase occupies the lecithin-rich region, close to the lecithin corner (with the exception of a small island of hexagonal phase) and coexists with neat water close to the water-lecithin axis. The remaining part of the phase map shows the three-phase coexistence of water, oil, and lamellar phase.
authors.affiliation: DISTAAM, Università del Molise, v. De Sanctis, I-861 00 Campobasso, Italy.
authors.forename: Ruggero
authors.initials: R
authors.lastname: Angelico
authors.forename: Andrea
authors.initials: A
authors.lastname: Ceglie
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Colafemmina
authors.forename: Francesco
authors.initials: F
authors.lastname: Lopez
authors.forename: Sergio
authors.initials: S
authors.lastname: Murgia
authors.forename: Ulf
authors.initials: U
authors.lastname: Olsson
authors.forename: Gerardo
authors.initials: G
authors.lastname: Palazzo
mesh_terms: D001672:Biocompatible Materials; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010168:Palmitates; D010713:Phosphatidylcholines / Q000737:chemistry*; D012212:Rheology; D014867:Water
chemical_list: D001672:Biocompatible Materials; D010168:Palmitates; D010713:Phosphatidylcholines; D014867:Water; C005060:isopropyl palmitate