The copper complex of captopril is not a superoxide dismutase mimic. Artefacts in DMPO spin trapping.

The effect of captopril and of its copper complex on several superoxide-dependent reactions used to detect and assay superoxide dismutase activity was studied, including pyrogallol and hematoxylin autoxidation and Nitro Blue Tetrazolium reduction. In none of these systems were superoxide dismutase-like properties of captopril/Cu apparent. Captopril/Cu decreased the yield of DMPO-OH adducts generated by KO2 but this effect may be due to the acceleration of the decay of the adduct by captopril/Cu.