Lipid hydroperoxide-dependent carbonyl formation. Reaction mixtures (1.0 ml) contained 1.0 mg BSA in 0.2 M K-PO4 buffer (pH 7.4) and the following additions as indicated in the figure: 10 mM ascorbate, 0.1 mM CuSO4, 0.1 mM FeCl2, 1.0 mM H2O2, and 1.0 mM linoleic-13-hydroperoxide. After 4 hr of incubation at room temperature, protein carbonyls were measured as described in Materials and Methods.