Simultaneous determination of vitamins A and E in rat tissues by high-performance liquid chromatography

A high-performance liquid chromatographic (HPLC) method to determine vitamins A, Ap and E simultaneously was developed with direct extraction of vitamins from rat tissues with n-hexane and probe sonicating. The dry residue was redissolved in chloroform-methanol. Vitamins A and Ap were detected by UV-Vis and vitamin E by fluorescence. Vitamin K, used as internal standard, was detected both the UV-Vis and by fluorescence. Standards and samples were checked for linearity giving correlation coefficients that were higher than 0.99 in the concentration range of 3.1-9.4 for vitamin A, 8.2-24.7 for vitamin Ap and 0.6-1.7 nmol/g in the case of liver extracts and 0.5-3.0 nmol/g in the case of placenta. The inta-assay precision (R.S.D) varied between 1.48 and 7.25, whereas inter-assay precision was between 4.99 and 7.03. Recoveries ranged between 94 +/- 8 and 107 +/- 5%. Results from the application of this method to different rat tissues having wide range of vitamin content are presented.