Colorimetric determination of vitamin D in some oily pharmaceutical preparations

Abstract

A colorimetric method for the determination of vitamin D, based upon the use of anisaldehyde-sulphuric acid as a colour reagent, has been developed. The method enables 0·1–0·5 mg of calciferol to be determined with a mean percentage recovery of 100·2 ± 1·44 per cent., and it avoids the difficulties met with in the antimony(III) chloride colour reaction.

Both methods, as applied to oily injections of vitamin D, are compared, and a statistical analysis of the results reveals that the proposed method is the more precise, and has an accuracy equal to that of the antimony(III) chloride method.