聚乙二醇接枝改性壳聚糖自组装纳米胶束的研究

Study on Self-Assembled Nano-Micelles Based on Poly(Ethylene Glycol)-Grafted Chitosan

利用聚乙二醇单甲醚(mPEG)对壳聚糖进行接枝改性,制得具有两亲性的接枝改性壳聚糖(mPEG-g-CS)衍生物,并通过自组装制得mPEG-g-CS纳米胶束。研究结果表明,在甲醛的作用下,mPEG与壳聚糖的-NH2发生了接枝反应获得取代度为27.4%的mPEG-g-CS样品,所得的mPEG-g-CS样品的结晶性与热稳定性均比壳聚糖弱。通过芘荧光探针分析发现,当mPEG-g-CS的浓度达到临界胶束浓度(CMC,0.014mg/mL),mPEG-g-CS分子自聚集成纳米胶束,且随着其浓度的增大,其自组装纳米胶束的粒径及其分布呈指数增加。

The amphiphilic chitosan derivative （mPEG-g-CS） was prepared through grafting methoxyl poly（ethylene glycol） （mPEG） onto chitosan （CS）. And also, the self-assembled nano-micelles were obtained for mPEG-g-CS. The results indicated that mPEG was reacted with the amino-groups of CS under the presence of formaldehyde,and the degree of substitution for mPEG-g-CS was 27.4 %, The crystallinity and thermal stability of the obtained mPEG-g-CS sample were weaker than that for CS. The results of pyrene fluorescence probe analysis showed that the self--aggregrated nano--micelles were obtained when the mPEG-g-CS content reached the critical micelle concentration （CMC,0. 014mg/mL）. And with the increase of its concentration, the particle size and its distribution of the self-assembled nano-micelles increased.