基因载体PEG化壳聚糖的制备及其表征

目的：用亲水性的聚乙二醇对壳聚糖进行改性，制备适用于基因转染的非病毒类裁体。方法：合成步骤共分三步。首先通过有机合成，将甲氧基聚乙二醇(mPEG)的羟基末端依次活化成为羧基和琥珀酰亚胺端基，形成mPEG-COOH活化物和mPEG-COONSu活化物；然后将亲水性的mPEG-COONSu活化物接枝到壳聚糖的氨基侧链上，得到改性了的壳聚糖-聚乙二醇接枝产物，应用波谱技术FTIR，^1H-NMR，^13C-NMR对中间产物和最终产物进行了表征。结果：在FTIR谱图上基本找到mPEG-COOH，mPEG-COONSu的特征峰；^1H-NMR再一次确认mPEG-COONSu的合成；^13C-NMR确认了壳聚糖-聚乙二醇接枝产物的存在。结论：mPEG-COONSu活化物通过接枝反应对壳聚糖进行改性，得到了PBG化壳聚糖。

The preparation and characterization of mPEGylated chitosan as gene vector

OBJECTIVE Modify the physical properties of chitosan in order to let it more suitable for non viral delivery system for gene therapy. METHOD By the way of organic synthesis, mPEG was activated; through the way of macromolecular polymerization, the modified mPEGylated chitosan was obtained through grafting hydrophilic mPEG spacer to the amino group of chitosan .The structures of the activated mPEG and mPEGylated chitosan were determined by modern spectrum technology, such as FTIR? 1 H NMR and 14 C NMR. RESULTS The activated mPEG COOH?mPEG COONSu and mPEGylated chitosan were prepared. Their structures were confirmed through a series of spectrum technologies. CONCLUSION mPEGylated chitosan can be obtained through grafting activated mPEG spacer to the amino group of chitosan.