Thermotropic behavior of dipalmitoylphosphatidylcholine-sulfatide liposomes.

The thermotropic behavior of multilamellar liposomes prepared from mixtures of sulfatide and dipalmitoylphosphatidylcholine has been studied by DTA calorimetry. The cooperative unit size and the enthalpy change of the main transition decrease concomitant with the increase of the sulfatide-phospholipid mole ratio. The origin of these effects and their dependence on the sulfatide content suggest that the in-plane distribution of sulfatide and the physical state of the lipid bilayer are affected by the sulfatide-phospholipid mole ratio.