Raman scattering in bilayers of saturated phosphatidylcholines. Experiment and theory.

Raman spectroscopy has been applied to a model biomembrane structure in order to obtain information about phospholipid hydrocarbon chain ordering. The intensity of the 1130-cm-1 Raman line obtained from a dipalmitoylphosphatidylcholine (DPPC) coarse aqueous dispersion has been measured as a function of temperature. The intensities of this line anther with the pretransition was observed. A theory of chain conformations as a function of temperature and rules for the assignment of Raman scattering intensities for this line have been constructed. Good agreement with the DPPC experimental data has been obtained. Predictions for the intensity of this line as a function of temperature from dimyristoyl- and distearoylphosphatidylcholine dispersions have also been made.