SPIN TRAPPING OF THE SUPEROXIDE RADICAL BY 4‐(N‐METHYLPYRIDINIUM) t‐BUTYL NITRONE

Abstract— The synthesis of 4‐(N‐methylpyridinium) t‐butyl nitrone (4‐MePyBN) and its use as a spin trap for superoxide radicals produced in aqueous solutions is reported (aN= 13.78 G, aHß= 1.65 G, and g = 2.0091). The half‐life of the spin adduct as a function of pH (83 s at pH 5.5, 78 s at pH 7.0, and 65 s at pH 8.0) the effects of iron salts, diethylenetriaminepentacetic acid (DETAPAC), and superoxide dismutase were examined, and comparisons made between 4‐MePyBN and 5,5‐dimethyl‐1‐pyrroline‐N‐oxide (DMPO) as spin trapping agents for the superoxide radical.