β-环糊精-聚丙烯酸的合成及对β-环糊精的包结与增溶性

Synthesis of β-Cyclodextrin-Polyacrylic Acid and Their Inclusion Behavior and Solubility Enhancement to β-Cyclodextrin

对β-环糊精(β-CD)进行改性,合成了一系列不同取代度的β-CD接枝的聚丙烯酸(PAA)聚合物,通过公式换算计算出β-CD的溶解度增加了6倍以上,并且随着接枝率的升高,其溶解度逐渐增加。研究证实,接枝到PAA链上以后,β-CD仍然能够有效地包结二乙烯三胺(DETA)分子,并且这种包结也具有pH依赖性。也就是说在改性前后,当pH值为11.5时,β-CD包合DETA的能力最佳,从1H-NMR上可以计算出其包合比为1∶1;而降低或者升高pH值后,都不能形成有效包合。

A series of β-cyclodextrin（β-CD） grafted polyacrylic acid（PAA） were prepared in order to improve the solubility of β-CD in water.It is found that the resulting β-CD-PAA shows great solubility enhancement of β-CD（the solubility of β-CD increases over 6 times）.The results of 1H-NMR confirm that 1∶1 β-CD inclusion complex with diethylenetriamine（DETA） is formed at pH 11.5 aqueous solution.And the inclusion complex could not form effectively at other pH conditions.The results of 2D-NOESY-NMR indicate that the β-CD groups still can form inclusion complex with DETA groups effectively when it is grafted onto polyacrylic acid chains.Moreover,the inclusion behavior between β-CD and DETA depends on the pH variation.