Studies on the Stability and Structure of β-cyclodextrin Vitamin D_2 Inclusion Complex

The inclusion complex of β\|cyclodextrin (βCD) with Vitamin D 2 (VD 2 ) was prepared in 60% ethanol aqueous solution. The accelerated tests of the inclusion complex βCD\|VD 2 were performed under strong light, high temperature and high humidity. The results showed that the content of VD 2 in the inclusion complex was still kept 85%~95% after two years, while that in the βCD and VD 2 mixture was just 17%~22%. It indicated that VD 2 in inclusion complex was much more stable than pure VD 2. Therefore, adding the inclusion complex βCD\|VD 2 into “Longmu” Zhuanggu Chongji, a medicine for children to prevent and cure rickets, can not only decrease the expense of VD 2, but also enhance the stability of the products. IR, X\|ray, DTA and UV techniques were used to characterize the structures of the inclusion complex. The results indicated that intermolecular hydrogen bonds formed in the βCD\|VD 2 inclusion complex.