表面改性聚乙烯亚胺-聚乙二醇/α-环糊精空心微球的制备与表征

Preparation and Characterization of Surface-Modified Poly(Ethylenimine)-Methoxy Poly(Ethylene Glycol)/α-Cyclodextrin Hollow Microsphere

首先合成了聚乙烯亚胺-聚乙二醇(PEI-b-mPEG)嵌段共聚物。然后利用α-环糊精(α-CD)与PEG和PEI之间不同的包合行为,构筑了一种以PEI为柔性链段,α-CD-PEG包合物为刚性链段的自组装空心微球PEI-b-mPEG/α-CD。最后,对PEI-b-mPEG/α-CD微球实施表面改性,得到了一种表面覆盖β-CD的空心微球。通过核磁共振、扫面电镜、透射电镜、原子力显微镜、X射线衍射和表面电位测试等方法对所得到的微球结构、性能等进行了表征。实验结果表明,这种微球还可以将喜树碱分子包合在外层β-CD内,预期在生物医学材料方面(如药物缓释和酶的固定化)会有较好的应用前景。

Poly( ethylenimine)-block-methoxy poly( ethylene glycol)( PEI-b-mPEG) was firstly synthesized via chemical coupling. Through the site-selective inclusion complexation between α-cyclodextrin( α-CD) and PEI-bmPEG,rod-coil complexes PEI-b-mPEG /α-CD were formed,resulting in the formation of hollow nanoparticles. Finally,β-cyclodextrin( β-CD) was introduced to the hollow microspheres via surface modification. Structures and properties of these particles were measured by nuclear magnetic resonance,scanning electron microscopy,transmission electron microscopy,atomic force microscope,X-ray diffraction,surface potential,etc. The resulting PEI-b-mPEG /α-CD-β-CD could entrap the hydrophilic molecules( for example,camptothecin) into its internal cavities and load the hydrophobic molecules into β-CD,showing great promise in the area of drug delivery system.