A high-performance liquid chromatographic method for the determination of tocopherol in plasma and cellular elements of the blood.

A rapid sensitive, and reproducible procedure is described for the analysis of alpha-tocopherol in blood cells and plasma using high-performance liquid chromatography and fluorometric detection. The cardinal feature for the increased sensitivity of this high-performance liquid chromatographic procedure is that the fluorometric analysis was carried out at a short excitation wavelength (205 nm) which increased the sensitivity of 20-fold over the usual excitation wavelength of 295 nm. Tocopherol levels can be measured in as little as 50 microliters of plasma and 200 microliters of erythrocytes. The tocopherol contentof plasma, red blood cells, platelets, polymorphonuclear leukocytes, and lymphocytes of normal subjects and subjects ingesting additional quantitites of vitamin E are reported. The values for the white cells are approximately 30 times higher than those of the red blood cells (polymorphonuclear leukocytes 4.47 +/- 0.62 micrograms/10(9), lymphocytes 3.89 +/- 0.85 micrograms/10(9), and erythrocytes 1.40 +/- 0.14 micrograms/10(10) cells). The tocopherol contents of the plasma and all the cellular elements of the blood were increased by oral feeding with vitamin E.