A method is described here for the simultaneous determination of retinol, -tocopherol, lycopene, and -carotene in human plasma. e effectiveness of various protein precipitants and extraction solvents was tested. Aer adequate sample preparation, the samples were injected directly into the HPLC system. e separation was realized on an analytical reversed-phase column with a UV-Vis detection. e analytical performance of this method was satisfactory. e intraassay and interassay coefficients of variation were below 10%. e recoveries were as follows: 97.0% (CV 2.4%) for retinol, 94.6% (CV 1.7%) for -tocopherol, 91.9% (CV 3.6%) for lycopene, and 93.9% (CV 4.2%) for -carotene. e levels of selected fat-soluble vitamins in plasma of patients with cardiovascular disease were measured and discussed
