内含脂质体的聚电解质微囊作为药物载体的制备与表征

目的:通过层层自组装技术(LBL)制备内含有脂质体的聚电解质微囊,并对其结构及其对药物的自沉积作用和释放性能进行研究.方法:利用共沉淀法制备碳酸钙模板,在其表面层层组装可生物降解的壳聚糖和海藻酸钠,去除碳酸钙模板后,得到内含脂质体的聚电解质微囊.通过透射电镜(TEM),扫描电镜(SEM)等对微囊的结构、自沉积作用及释放性能进行表征.结果:TEM和SEM显示本实验成功得到了内含脂质体的聚电解质微囊;随着多柔比星给药浓度的增高,载体的囊内药物浓度呈非线性增加,在给药浓度为1 mg·ml-1的条件下,微囊内的最高药物浓度达520.1 mg·ml-1;48 h内,微囊在不同pH(5.0,6.5,7.4)的PBS中的累积释放百分率分别达到59.2%,54.3%,44.8%.结论:内含脂质体的聚电解质微囊具有良好的自沉积作用和释放能力,作为新型的药物载体具有较好的应用前景.

Preparation and Characterization of Liposomes containing Polyelectrolyte Microcapsules as Drug Carriers

Objective： To prepare liposomes-containing polyelectrolyte mierocapsules by layer-by-layer self-assemble technique, and study the structure, spontaneous deposition and release profile. Method： The polyelectrolyte microcapsules were fabricated by deposition of oppositely charged chitosan and alginate onto the liposomes-eontaining calcium carbonate colloidal particles in a layer-by-layer way followed by the removal of the template cores with disodium ethylenediaminetetraacetic acid. The structure, spontaneous deposition and release profile of the microeapsules were characterized by TEM and SEM. Result： TEM and SEM images revealed that liposomes- containing polyelectrolyte microeapsules were obtained successfully. The concentration of doxorubicin in the microeapsules was in- creased with the increase of doxorubiein concentration, and the highest concentration of doxorubiein in the mierocapsules could reach 520.1 mg· ml-1 with the doxorubicin concentration of 1 mg· ml-1. The cumulative release amount of doxorubicin from the microcapsules in 48 h was 59.2% , 54.3% and 44.8% in PBS with pH of 5.0, 6.5 and 7.4, respectively. Conclusion： The liposomes-eontaining polyelectrolyte microcapsules show promising spontaneous deposition and release ability, stiggesting good application prospects as novel drug carriers.