【摘要】 目的采用微波法合成PLA-PEG-PLA,并以该嵌段共聚物为基质制备ASA/PLA-PEG-PLA载药微球和ASA-Fe3O4/PLA-PEG-PLA载药微球,考察磁性载药微球和非磁性载药微球的药物缓释性能。方法通过傅立叶变换红外光谱(FT-IR)、核磁(NMR)对微波法合成的PLA-PEG-PLA的微观结构进行了表征分析。采用乳化-溶剂挥发法制备了ASA/PLA-PEG-PLA载药微球,通过正交设计实验优选载药微球的最佳制备条件,在此基础上利用单微乳法制备的Fe3O4纳米粒子制备了ASA-Fe3O4/PLA-PEG-PLA载药微球。通过透射电子显微镜(TEM)、X-射线衍射(XRD)对Fe3O4纳米粒子进行微观结构表征和性能分析。采用傅立叶变换红外光谱(FT-IR),扫描电子显微镜(SEM)对制备的载药微球进行了微观结构的表征和分析。结果微波法合成的PLA-PEG-PLA是一种三嵌段共聚物。载药微球呈规则球形,表面光滑,粒径分布较均匀,平均粒径约为20μm。体外模拟释药试验表明ASA/PLA-PEG-PLA载药微球和ASA-Fe3O4/PLA-PEG-PLA载药微球24h释药率分别为69.16%和100%。结论以微波法合成的PLA-PEG-PLA作为药物载体具有明显的缓释作用。ASA-Fe3O4/PLA-PEG-PLA磁性载药微球比ASA/PLA-PEG-PLA非磁性载药微球具有较快的药物释放速率。更多还原

【Abstract】 Objective PLA-PEG-PLA was synthesized by microwave-assisted polymerization.Drug-loaded microspheres were prepared by using this copolymer as matrix.The drug release properties of the magnetic drug-loaded microsphere and non-magnetic drug-loaded microsphere were observed.Methods The microstructure of synthesized PLA-PEG-PLA was characterized by FT-IR,1H-NMR.ASA/PLA-PEG-PLA drug-loaded microspheres were prepared by emulsion-solvent evaporation method.The optimum experimental conditions of drug-loaded microspheres were screened by orthogonal experiment.Magnetic ferroferric oxide(Fe3O4) was prepared by water-in-oil microemulsion processing and characterized by TEM and XRD.The microstructure of drug-loaded microspheres was characterized and analyzed by FT-IR,SEM.Results The polymer was synthesized by microwave-assisted method was a ABA type copolymer(PLA-PEG-PLA).The drug-loaded microspheres were of regular sphere and smoothly surface.Their distribution were even and the average diameter was 20μm.The drug release of two kinds of drug-loaded microspheres were studied by in-vitro release method.The drug cumulative release ratio of ASA/PLA-PEG-PLA microspheres and ASA-Fe3O4/PLA-PEG-PLA magnetic microspheres were 69.16% and 100%,respectly.Conclusion The PLA-PEG-PLA which was synthesized by microwave-assisted polymerization as a drug carrier has obvious sustained-release property.The drug release rate of ASA-Fe3O4/ PLA-PEG-PLA magnetic drug-loaded microsphere is bigger than that of ASA/PLA-PEG-PLA non-magnetic drug-loaded microsphere.更多还原