Simplified HPLC-UV method for the determination of alfa-tocopherol in plasma.

Vitamin E, known for its great nutritional importance, is normally included in animal diets as DL-tocopherol acetate. The authors propose a method that makes it possible to determine the concentration of vitamin E in plasma without saponification. This method enable to avoid aggressive treatments on the analyte and complex procedures; it detects vitamin E only in form of DL-x-tocopherol. Lipoproteins of analysed plasma were denaturised by methanol. Vitamin E was extracted by petroleum ether in presence of NaCl. The extract was dried by rotavapor at 45 °C, solubilized by methanol and injected in HPLC (C18 column, reversed phase). The quantitative determination was carried out by UV detector settled on 294 nm. Tests of repeatability inter-analysis and intra-analysis gave coefficient of variability (CV%) respectively of 1.64 and 2.41%. The mean recovery was 100%.