[Effect of dicarboxylic lecithins on liposomes]

We have investigated the effect of dicarboxylic lecithins on liposomes prepared from egg-lecithins and their incorporation into liposome preparation. In the presence of phospholipids, liposome cell permeability to glucose is five times higher than in controls. The incorporation of dicarboxylic lecithins into liposomes at a molar concentration of 50 molecules per cent reduces by 60% the amount of glucose trapped inside the liposomes. Measurements of ovolecithin-glutaryl-lecithin liposomes stability show that stable structures are formed at a molar concentration of 70 molecules per cent in the presence of cholesterol. On the contrary, the liposomes prepared in the absence of cholesterol are not stable at a molar concentration of 50 molecules per cent. Measurements of sedimentation of mixed dispersions of monocarboxylic lecithins and glutaryl-lecithins show that glutaryl-lecithins must be in the form of micelles to solubilize the phosphatidyl cholines.