Two perparation procedures were carried out to encapsulate norfloxacin into liposomes.The interaction of norfloxacin with phospholipids in liposomes was investigated by using differential scanning calorimetry and conformational analysis.The long term stability of liposomal drug was studied by measuring the leakage of norfloxacin at various storage conditions.These results indi-cated that,for liposomes prepared through the ethanol injection and freeze-drying processes,norfloxacin was not only encapsulated within the liposomes cavity but also bound to the lipid bilayer.Thus,the drug encapsulation inside liposomes was increased.For the long term stability,the results suggested that liposomes should be stored in the state of lyophilized powder at lower temperature and reconstitute by adding double-distilled before used. 本研究是採用兩種製造過程將norNoxacin包埋於微脂粒中，再以埶分析儀與構造分析來探討norNoxacin與微脂粒中之磷脂質的交互作用;至於微脂粒包覆型藥物之長期安定性，則是藉由在不同的貯存條件下，檢測nornoxacin的滲漏自情形。上述實驗的結果指出，微脂粒若採行併合乙醇注入與冷凍乾燥的製程，nornoxacin不僅會包覆於微脂粒的內部空腔中，同時也常會包埋於脂質雙層的分子內，進而提升了微脂粒之藥物的包覆率;為了長期的安定性，本研究建議，微脂粒應以凍晶乾燥之粉體在較低溫度下進行貯存，使用前再加入二次蒸餾水還原。
