Raman and infrared spectroscopic study of phytantriol and phytantriol-water cubic phases

Abstract

Phytantriol and phytantriol-water cubic phases were studied by vibrational spectroscopy (FT-IR and FT-Raman). Assignments of the bands were performed based on the OH/OD isotopic substitution, measurements of FT-Raman polarization spectra and temperature-dependent spectral changes. The conformation and H-bonding sensitive modes have been identified. It has been shown that the frequency of methylene deformation vibration increases in liquid-crystalline cubic phases as compared with melted phytantriol, indicating an alteration of the interactions between alkyl chains in the lipidic layer. Analysis of the high frequency FT-Raman spectral range revealed broadening of the CH3 asymmetric stretching band of cubic phases due to an increased heterogeneity of the local environment of methyl groups. Keywords: phytantriol, cubic phases, FT-IR, FT-Raman, hydrogen bonding