Simple Assay for the Level of Total Lipid Peroxides in Serum or Plasma

As is well-recognized, lipid peroxidation is initiated by the abstraction of a hydrogen atom from a polyunsaturated fatty acid, and proceeds via free-radical species to form the primary stable product, lipid hydroperoxide, and then the secondary stable product, lipid aldehyde, as depicted in Fig. 1 . To check lipid peroxidation in the body, investigate free radical injury, or aid in the diagnosis of lipid peroxide-mediated diseases, one of the most routine test samples is serum or plasma. In serum and plasma, however, free-radical species involved in the process shown in Fig. 1 all disappear because of their short lifetime, and only stable substances remain. Even such stable substances are liable to decompose to some extent, and, therefore, prolonged treatment or organic solvent-extraction should be avoided. Accordingly, the principle of the procedure presented here is to react these lipid peroxides with a suitable reagent after eliminating other reactive or disturbing substances.