磁性PCL-PEG-PCL微球的制备及释药性研究

Research on the preparation and drug delivery of magnetic PCL-PEG-PCL Microspheres

以聚乙二醇引发ε-己内酯开环聚合得到聚己内酯-聚乙二醇-聚己内酯(PCL-PEG-PCL)共聚物,双乳化-有机溶剂挥发法制得载药磁性PCL-PEG-PCL微球,并对微球进行一系列表征及研究其磁响应释药行为。FT-IR结果表明PEG接枝上PCL;GPC结果表明共聚物分子量分布均匀;SEM结果表明微球呈球性良好;XRD结果表明微球包载且未改变纳米Fe_(3)O_(4)粒子晶型;TEM结果表明磁性PCL-PEG-PCL微球分散性较好,Fe_(3)O_(4)纳米粒子均匀分布在其中;TGA结果表明投磁量越大,磁余量越多;CLSM结果表明微球包载FITC荧光素,FT-IR进而表明微球能包载盐酸阿霉素。体外释药实验表明载药微球累积释药率随着磁含量的增大而增大,释药机理符合Ritger-Peppas模型。

The copolymer of PCL-PEG-PCL was prepared by ring-opening polymerization of ε-caprolactone using polyethylene glycol as initiator.The magnetic PCL-PEG-PCL microspheres containing drug were prepared by double emulsification-organic solvent evaporation method,and its properties were characterized and magnetic response release behavior were studied.FT-IR results showed that the copolymers contained the segments of PCL and PEG.GPC showed that the molecular weight distribution of copolymer was uniform.From the result of the SEM photographs,microspheres were spherical.TEM images showed that the magnetic PCL-PEG-PCL microspheres had good dispersibility,and Fe_(3)O_(4)nanoparticles were evenly distributed.XRD results showed that the microspheres successfully coated Fe_(3)O_(4)nanoparticles without changing the crystal structure of Fe_(3)O_(4)nanoparticles.The results of thermal analysis showed that the greater magnetic capacity,the greater the remaining amount of Fe_(3)O_(4)nanoparticles.The CLSM results showed that microspheres were successfully loaded with FITC fluorescein.FT-IR indicated the microspheres could be loaded with adriamycin hydrochloride.In vitro drug release experiments showed that the cumulative drug release rate of drug-loaded microspheres increased with the increase of magnetic content,and the drug release mechanism was consistent with Ritger-Peppas model.