FIGURE 14.

Detection of peroxy species from the reaction between singlet oxygen and GSH (A), GSSG (B), cysteine (C), and cystine (D). Incubation mixtures contained rose bengal (10 μm) and CBA (0.8 mm) and were photolyzed in the presence or absence of an appropriate amino acid or peptide (1 mm), catalase (250 units/ml), deuterated water (∼60%), and azide ion (10 mm) (as indicated). Insets, photolyzed mixtures (photolysis time 10 min; 10 μm rose bengal) of GSH (1 mm) (A) or cysteine (C) assayed with FOX reagent. Samples contained phosphate buffer (50 mm, pH 7.4) and DTPA (0.1 mm) (except when FOX reagent was used) and were continuously oxygenated during photolysis. Error bars, S.D.