Vitamin D2, also known as ergot calcitol. It can promote the absorption of calcium and phosphorus in intestine, promote calcification and ossification. It is mainly used to treat and prevent rickets, osteomalacia and other diseases in clinic. Vitamin D2 is not stable and insoluble in water, which limits its application in pharmaceutical preparations, especially in aqueous solutions.
Vitamin D2 and hydroxypropyl beta-cyclodextrin were weighed at 1:2 mole ratio. Hydroxypropyl beta-cyclodextrin was dissolved in water. Vitamin D2 was added to mix for 0.5 H. The microporous membrane was filtered. The filtrate was frozen in the refrigerator and then dried in a vacuum freeze dryer. The dried matter was crushed. Compared with vitamin D2 ethanol aqueous solution, the stability of vitamin D2 hydroxypropyl beta-cyclodextrin inclusion complex aqueous solution to high temperature and light was significantly improved. The contents of vitamin D2 in the inclusion complex aqueous solution and ethanol aqueous solution were 74.4% and 41.2% respectively after six months storage under the experimental conditions.
Hydroxypropyl beta-cyclodextrin is a derivative of beta-cyclodextrin. It is a commonly used inclusion material because of its good water solubility, remarkable solubilization effect and little toxicity. However, the aqueous solution of vitamin D2 inclusion complex degraded rapidly under light conditions, so its water-soluble preparations should be kept away from light.