The stability of polymerizable and polymerized liposomes, prepared with butadienephosphatidylcholine synthesized from dodecane carboxaldehyde, triethyl-4-phosphonocrotonate and glycerophosphorylcholine, were investugated in terms of absorbance of visible light.
The polymerizable lipid formed multilamellar vesicles upon dispersion in water and changed to small unilamellar vesicles (SUV) by ultransonication, and polymerized by UV irradiation, covalently cross-linking the individual lipid molecules.
The freshly sonicated liposomes of both polymerizable and egg lecithin showed linear relationships of their light absorbance against $(wavelength)^{-4}$ following the Rayleight theory for small spherical particles with mondispersed size distribution, but their turbidities were intensified upon incubation indicating liposomal coalescence. The intensity and the rate of change in turbidity for polymerizable vesicles were greater than those of egg lecithin, because of inco-operation of the butadiene group curvature formation.
Once polmerized, the change of turbidity was significantly suppressed in incubation or alcohol dilution because of the formation of stable structures, while initial destabilization during polymerization has been observed.
