Liquid Chromatographic Analysis of All-Rac-α-Tocopheryl Acetate, Tocopherols, and Retinyl Palmitate in SRM 1846

A liquid chromatographic method is described for the analysis of all-rac-α-tocopheryl acetate, tocopherols, and retinyl palmitate in the infant formula standard reference material 1846. The vitamins are extracted in isopropanol and hexane/ethyl acetate without saponification and quantitated by normal phase chromatography with fluorescence detection. Retinyl palmitate, all-rac-α- tocopheryl acetate, and naturally occurring tocopherols are quantitated isocratically with a mobile phase of 0.5% isopropanol in hexane. The results were within the certified ranges for all-rac-α-tocopheryl acetate and retinyl palmitate. Recoveries averaged 97.5% for retinyl palmitate and 101% for all-rac-α- tocopheryl acetate (n = 20).