薄荷脑-羟丙基-β-环糊精包合物的拉曼光谱分析

Study on the inclusion compound of menthol with hydroxy propyl-beta-cyclodextrin by Raman spectroscopy

目的:使用拉曼光谱分析鉴定羟丙基-β-环糊精对薄荷脑包合后的产物,确定薄荷脑-羟丙基-β-环糊精包合物形成并表述其分子结构信息。方法:采用RENISHAW RM-1000型激光共聚焦拉曼光谱仪和RENISHAW inVia Raman Micro-scope显微拉曼光谱仪分别采集了薄荷脑、羟丙基-β-环糊精以及薄荷脑-羟丙基-β-环糊精包合物不同配比时制备的包合物的拉曼光谱并进行对照分析。结果:将薄荷脑与它的羟丙基-β-环糊精包合物的拉曼光谱互相对照,薄荷脑的许多特征峰在包合物中消失了,而另一些特征峰分别向高波数或低波数方向发生了位移;将羟丙基-β-环糊精与薄荷脑包合物的拉曼光谱相比较,可以看出虽然大多数峰的形状、数量和强度都很相似,但仍有明显差异。结论:拉曼光谱表征说明薄荷脑与羟丙基-β-环糊精分子间相互作用形成氢键,使薄荷脑嵌入羟丙基-β-环糊精的疏水空腔从而形成了包合物,增加了薄荷脑的极性从而增强了它的溶解度和吸收速率。

Objective：To identify the inclusion compound of menthol with hydroxypropyl - beta - cyclodextrin in the solid state with Raman spectroscopy and to reveal the structural features. Methods：The Raman spectra of men- thol, hydroxypropyl -beta -cyclodextrin and the inclusion compound was obtained with RENISHAW RM -1000 la- ser confocal Raman spectrometer and RENISHAW inVia Raman Microscope. Results： To compare the Raman spectrum of menthol with the Raman spectrum of its inclusion compound, some marker bands of menthol disap- peared in the Raman spectrum of the inclusion compound and other marker bands were shifted. To compare the Ra- man spectrum of hydroxypropyl - beta - cyclodextrin with the Raman spectrum of the inclusion compound, they have significant differences in spite of their similarity. Conclusion： The Raman spectra indicated that menthol stabi- lized by interaction with hydroxypropyl -beta -cyclodextrin via hydrogen bonds and form the inclusion compound. The dipolar character of the inclusion compound improves the solubility and the dissolution rate of menthol and thus its rate of absorption