Stopped Flow Spectrophotometric Observation of Superoxide
نویسندگان
چکیده
There are few ways to develop a high concentration of superoxide in solutions of physiological significance, and by far the most useful of these, pulsed radiolysis of oxygenated solutions [1 ], requires very specialized and expensive research equipment. One of the long term goals of this laboratory has been to develop alternative procedures for examining the chemistry of superoxide ion in aqueous solution [2]. We now report some preliminary results obtained with a stopped-flow spectrophotometric system which mixes superoxide, stabilized in aprotic solvents, into aqueous solutions and allows direct photometric observation of the superoxide. In this preliminary communication we present results on (a) the second-order dismutation of superoxide in the pH 7-11 range, (b) the kinetic behavior of bovine superoxide dismutase in this pH region, and (c) the decay of O~ in the presence of H202 which show that the Haber-Weiss [3] reaction
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