High-performance liquid chromatographic analysis of vitamins I: quantitation of cholecalciferol or ergocalciferol in presence of photochemical isomers of the provitamin and application to cholecalciferol resins.

A high-performance liquid chromatographic (HPLC) procedure was developed for the quantitative determination of cholecalciferol or ergocalciferol in the presence of the photochemical isomers of the provitamin. Separation is also achieved from various common reaction products encountered in the vitamin synthesis as well as other fat-soluble vitamins. The method was applied to the routine analysis of cholecalciferol resins, and experimental data are set forth. A comparison of the HPLC method to the AOAC biological and chemical procedures shows that the HPLC method most closely approximates the antirachitic activity of a cholecalciferol sample. The specificity, sensitivity, and reproducibility of the method make it applicable to various vitamin samples containing cholecalciferol or ergocalciferol.