论文部分内容阅读
合成了一系列亲水、疏水链段质量比例不同的聚乙二醇-聚乳酸(PEG-PLA)嵌段共聚物胶束,并以两性霉素B为模型药物制备了载药胶束.为获得稳定性良好的、可长期储存的载药胶束剂型,对胶束进行了冷冻干燥.使用不同浓度的糖类(包括甘露糖、海藻糖、葡萄糖)、泊洛沙姆188(Pluronic F68)、聚乙二醇作为冻干保护剂,以冻干产品的重分散性、冻干前后胶束的粒径及多分散性为指标评价各种保护剂的保护效果.结果发现,当嵌段聚合物中聚乳酸链段的质量百分比小于或等于聚乙二醇时,糖类、Pluronic F68和PEG均可以起到有效的冻干保护作用;而对于聚乳酸链段质量比例较大的共聚物胶束,只有PEG和Pluronic F68能够起到较好的冻干保护作用.对载药胶束体外释放研究表明,聚合物胶束的体外释放缓慢,符合一级动力学特征.
A series of polyethylene glycol-polylactic acid (PEG-PLA) micelles with different mass ratios of hydrophilic and hydrophobic segments were synthesized and drug-loaded micelles were prepared with amphotericin B as model drug. The micelles were freeze-dried with stable and long-term drug-loaded micellar formulations.Using different concentrations of sugars (including mannose, trehalose, glucose), Pluronic F68 , Polyethylene glycol as a lyoprotectant to evaluate the protective effect of various protective agents on the basis of the redispersibility of the lyophilized product, the particle size and the polydispersity of the micelles before and after lyophilization, and found that when the block polymerization When the mass percentage of polylactic acid segment in the product is less than or equal to that of polyethylene glycol, both Pluronic F68 and PEG can effectively freeze-dry and protect; while for the polylactic acid segment, Only PEG and Pluronic F68 can protect the cells from lyophilization.Extracellular release of drug-loaded micelles shows that the release of polymer micelles in vitro is slow and consistent with the first-order kinetic characteristics.