입체구조적으로 안정화된 리포좀의 특성 및 혈장내 안정성

Characterization of Sterically Stabilized Liposomes and Their Stability in Rat Plasma in Vitro

Sterically stabilized liposomes (SSL) composed of distearoylphosphatidylcholine, cholesterol, dicetylphosphate and distearoylphosphatidylethanolamine-N-poly (ethyleneglycol) 2000 (DSPE-PEG 2000) were made by reverse phase evaporation method to prolong biological half-life and decrease toxic side effect of drug. Streptozocin (STZ), a water-soluble antitumor agent with short half-life, was selected as a model drug. The size of SSL was controlled by polycarbonate extrusion to 100nm which is adequate size for long circulation in plasma. The release rate of drugs from SSL in PBS was evaluated. And the stability of STZ-containing liposomes against drug leakage into rat plasma was evaluated in order to investigate the interaction of liposome and plasma protein. Incorporation of DSPE-PEG 2000 into conventional liposomes significantly decreased the drug leakage into rat plasma.