Determination of vitamins A and E in liver tissue.

A simple, efficient and robust method for the simultaneous determination of the two vitamins A and E in liver tissue has been developed and evaluated. The assay consists of a saponification step followed by a single extraction of the resulting solution with a mixture of n-hexane/toluene. The vitamins are quantified in the extract using two separate HPLC lines running on straight phase mode. The eluted compounds were detected with a fluorescence detector. Recoveries of spiked samples were found to be 92.4% for vitamin A and 95.2% for alpha-tocopherol. The coefficient of variation was found to be +/- 4.27% for retinol and +/- 4.64% for alpha-tocopherol. The described analytical method has proven to be very effective and fast, enabling the processing of a large number of samples within a short period of time. It is highly specific and sensitive covering a wide range of different concentrations in the samples. It may be applied therefore in routine assays of samples with great variability concerning the vitamin concentrations in the tissue.