Formulation of liposomes with a soybean-derived sterylglucoside mixture and cholesterol for liver targeting

In this study, we investigated a liposomal formulation of dipalmitoylphosphatidylcholine (DPPC) with a soybean-derived sterylglucoside mixture (SG) and cholesterol (Ch) for targeting the liver in mice. We found two distribution profiles of liposomes (reverse-phase evaporation vesicles, REV) in the liver depending on the concentration of Ch and SG in vivo; Ch tends to enhance liposomes containing 10 mol% SG accumulation in the liver, but to decrease those containing 20 mol% SG, and it prolongs the circulation in blood. Dicetylphosphate did not enhance liver targeting by liposomes with SG and Ch. More DPPC/SG/Ch-liposomes (6:1:3) were significantly taken up by cultivated hepatocytes than DPPC/SG/Ch-liposomes (6:0:4), suggesting a glucose residue. The optimal composition for the maximal liver targeting was a mixture of 0.2 micron DPPC/SG/Ch-liposomes (REV) at a molar ratio of 6:1:3. This composition of liposomes was distributed 3 times greater in hepatocytes than non-parenchymal cells 1 h after intravenous injection.