Biocompatible lecithin organogels: structure and phase equilibria

Langmuir. 2005 Jan 4;21(1):140-8. doi: 10.1021/la047974f.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biocompatible Materials*
  • Magnetic Resonance Spectroscopy
  • Molecular Structure
  • Palmitates
  • Phosphatidylcholines / chemistry*
  • Rheology
  • Water

Substances

  • Biocompatible Materials
  • Palmitates
  • Phosphatidylcholines
  • Water
  • isopropyl palmitate