聚乙二醇单甲醚接枝壳聚糖自组装纳米球的制备*

目的:合成聚乙二醇单甲醚接枝壳聚糖(monomethoxy poly(ethylene glycol)-grafted-chitosan,mPEG-g- CS),并制备自组装纳米球。方法:利用甲醛连接法将聚乙二醇单甲醚(monomethoxy poly(ethylene glycol),mPEG)接枝干壳聚糖(ehitosan,CS)分子,得到聚乙二醇(poly(ethylene glycol),PEG)改性的壳聚糖衍生物,并通过傅立叶红外光谱仪(Fourier transform infrared spectroscopy,FT-IR),核磁共振仪(proton nuclear magnetic resonance,~1H-NMR)对产物进行结构表征;采用超声透析法制备自组装纳米球,并通过透射电镜(transmission electron microscopy,TEM),动态激光粒度分析仪(dynamic laser light scattering,DLLS)表征了纳米球的形态和粒径;以芘为荧光探针,通过荧光检测分析测定了mPEG-g-CS的临界胶束浓度(critical micellar concentration,CMC)。结果:通过FT-IR,~1H- NMR确证了接枝产物的存在;mPEG-g-CS在水溶液中能够自组装形成球状纳米胶束,平均粒径为250 nm。结论:通过甲醛连接法制备mPEG-g-CS,具有制备方法简捷、反应周期短、易操作的优点。利用该产物制备的纳米球有望成为长循环纳米药物载体。

Preparation of self-assembled monomethoxy poly (ethylene glycol ) -grafted-chitosan nanoparticles

Objective:To synthesize methoxy poly(ethylene glycol)-grafied-chitosan and prepare its self-assembled nanoparticles.Methods:The monomethoxy poly(ethylene glycol)-grafted-chitosan was synthesized by formaldehyde linking method.The chemical structure of polymer was characterized by the fourier transform infrared spectroscopy(FT-IR) and proton nuclear magnetic resonance (~1H-NMR).The self-assembled nanoparticles was prepared by probe sonication-dialysis method and analyzed by transmis- sion electron microscopy (TEM),dynamic laser light scattering (DLLS).The critical micellar concen- tration(CMC) of monomethoxy poly(ethylene glycol)-grafted-chitosan was determined by measuring the fluorescence intensity of the pyrene as a fluorescent probe.Results:The chemical structure of polymer was confirmed by FT-IR and ~1H-NMR.The self-assembled nanoparticles were spherical and their average diameter was about 250 nm.Conclusion:The preparation procedure of monomethoxy poly( ethylene gly- col)-grafted-chitosan was easy to be operated.This novel nanoparticle system was promising to be a good long-circulating drug carrier.