SIMULTANEOUS DETERMINATION OF VITAMIN-D-3, VITAMIN-E AND VITAMIN-K1, AND RETINYL PALMITATE IN CATTLE PLASMA BY LIQUID-CHROMATOGRAPHY WITH ANARROW-BORE COLUMN

A reversed-phase high performance liquid chromatographic method is des cribed for the simultaneous determination of vitamins D-3, E and K-1 a nd retinyl palmitate in plasma. Narrow-bore columns are recommended be cause this alternative provides a good separation efficiency, plus gre ater economy and sensitivity. Detection limits for individual vitamins range from 0.42 to 2.8 ng. All vitamins were separated in less than 9 min. Recovery studies showed good results for all solutes (88.8-100.3 %) and the intra-day coefficients of variations ranged from 1.0 to 4.5 %. This method permits the simple determination of fat-soluble vitamin s using 1 ml of cattle heparinized plasma.