Effect of sucrose on the optical properties of dipalmitoylphosphatidylcholine

The gel to liquid crystal phase transition of dipalmitoylphosphatidylcholine (DPPC) has been followed by the change in absorbance at 400 nm; this change is due to the change in lipid light scattering properties during the transition. The effect of sucrose on the change in absorbance during the transition of DPPC has been investigated. It has been shown that the presence of sucrose or glycerol in the multilamellar liposome suspension increases the change in absorbance due to the main transition, decreases the total absorbance, and decreases the change in absorbance due to the pretransition. This effect of sucrose and glycerol is shown to be an optical effect which is correlated with solvent index of refraction.