Abstract
An acid clay dried at 105-110℃ was packed in a chromatographic column, 6 cm in height and 0.7 cm in diameter. At first 15 ml of 7% ethanol-hexane was passed through the colomn, followed by 10 ml of 10% ethyl ether-hexane. The column thus treated could be used to separate vitamin D_2 from vitamin A. The recoveries of vitamin D_2 were 93-94%. The amount of vitamin A in the sample could not exceed 800 I. U.. A small amount of destruction products of vitamin A was found to be eluted in the vitamin D_2 fraction, thus samples with less than 400 I. U. of vitamin D_2 could not be applied to this chromatography. Cholesterol could be separated from vitamin D_2 by the above procedure.
