Quantitative determination of tocopherols by high-speed liquid chromatography

A high-speed liquid chromatographic method for the determination of alpha-, beta-, gamma- and delta-tocopherols using a spectrophotometer or a spectrofluorometer, is described. The best results were obtained using a 2.3 mm i.d. x 500 mm normal phase partition column, JASCO-PACK WC-03-500 and a spectrofluorometer as a specific detector. A mixture of diisopropyl ether and n-hexane (2:98) was used as the mobile phase. A flow rate was set at 0.8 ml/min. A mixture of pure alpha-, beta-, gamma- and delta-tocopherols or natural tocopherols in vegetable oils were separately determined by this method.