利用醛化壳聚糖(CS-CHO)的醛基与聚乙烯亚胺(PEI)的氨基间的反应形成高分子缀合物来制备低毒,又有一定效果的基因载体。合成了醛化度为29.6%的CS-CHO,并通过傅立叶红外光谱及核磁共振的方法对其结构进行了表征。采用分子量为600g/mol的PEI与该CS-CHO进行反应,研究了CS-CHO与PEI的投料比、投料顺序对接枝度的影响,实验结果表明,投料比对接枝度的影响很大,在PEI与CS-CHO的物质的量比小于2∶1时,接枝度随着PEI的量的增加而增加,最大为41.87%,但之后继续增加PEI的量而接枝度由41.87%减小到26.98%。投料顺序对接枝度的影响则相对较小,物质的量比为2∶1的CS-CHO与PEI直接混合获得的接枝度最大,为29.21%。 The use of the reaction of the aldehyde group of the aldehyde-chitosan (CS-CHO) with the amino group of polyethyleneimine (PEI) to form a polymer conjugate to prepare a low-toxic genetically modified gene vector. CS-CHO with a degree of aldylation of 29.6% was synthesized and its structure was characterized by Fourier transform infrared spectroscopy and nuclear magnetic resonance. The effect of the feeding ratio of CS-CHO and PEI on the grafting degree was investigated by PEI with molecular weight of 600g / mol and CS-CHO. The experimental results show that the feeding ratio has a great influence on the grafting degree . When the ratio of PEI to CS-CHO was less than 2:1, the degree of grafting increased with the increase of PEI up to 41.87%, but then the amount of PEI continued to increase from 41.87% Reduced to 26.98%. The degree of grafting was relatively small with the order of feeding. The degree of grafting obtained by direct mixing of CS-CHO and PEI with the mass ratio of 2:1 was 29.21%.