抄録
An analytical method for the determination of vitamin D in the presence of vitamin A and α-tocopherol was investigated. After saponifying preparations, extracting the unsaponifiable matters and dissolving in iso-propanol, the solution was subjected to the column chromatography using Amberlyst A-26 as a strongly basic anion exchange resin. Vitamin A alcohol and vitamin D were eluted with iso-propanol, whereas α-tocopherol was remained in the column. After evaporating solvent from the eluate, the residue was dissolved in chloroform and then treated with gel filtration through a Sephadex LH-20 column to eliminate vitamin A alcohol and α-tocopherol degradation products accompanied with vitamin D. The vitamin A degradation products still accompanied with vitamin D were removed by means of the adsorption chromatography through a Florex XXS column. Then, vitamin D was determined by Nield's antimony trichloride color reaction applying Wilkie's color inhibitor method. When this proposed method was applied to the model preparations made by mixing vitamin D2, vitamin A palmitate and α-tocopheryl acetate, satisfactory results were obtained. It was also confirmed that this method was available for the determination of vitamin D in pharmaceutical preparations.
