FIGURE 16.
The competition kinetics analysis of the reaction between 1O2-derived hydroperoxides and ebselen. Shown is the dependence of COH peak area on the concentration of ebselen for the photogenerated hydroperoxides of tyrosine (A), 4-hydroxyphenylacetic acid (B), tryptophan (C), and histidine (D). The solid line represents the result of nonlinear fitting. Insets, results of fitting the experimental data using the linear relationship. Photolyzed samples were preincubated with catalase (250 units/ml) and diluted 10 times with solution containing CBA (0.8 mm) and ebselen (0–0.2 mm). All samples were prepared in phosphate buffer (50 mm, pH 7.4) containing DTPA (0.1 mm). Error bars, S.D.