Effects of Storage Conditions and Hemolysis on Vitamin E Concentrations in Porcine Serum and Liver

Vitamin E (α-tocopherol) is an antioxidant vitamin important in protecting unsaturated fatty acids in lipid membranes from peroxidation. Variation in collection, storage, and shipping conditions of samples can potentially lead to breakdown of vitamin E prior to analysis. Therefore, the purposes of this project were 1) to determine the stability of vitamin E in refrigerated and frozen porcine liver and serum and 2) to evaluate the effects of red blood cell (RBC) hemolysis on porcine serum vitamin E concentrations. Porcine liver and nonhemolyzed serum were collected and stored refrigerated or frozen. Samples were analyzed for vitamin E immediately or on days 2, 3, 7, or 14. In addition, porcine RBCs were added to normal serum at concentrations from 1 × 10 6 to 1 × 10 9 RBC/ml and hemolyzed by freeze-thaw prior to analysis for vitamin E or products of lipid peroxidation.