The reaction of NO· with O2·− and HO2·−: A pulse radiolysis study

The reactions of NO·− with O2·− and with HO2·− were studied using the pulse radiolysis technique under pseudo first order conditions where ([O2·−]o + [HO2·−]o) > [NO·]o at pH 3.3–10.0. The rate constant of the reaction of NOʹ with O2· was determined both by monitoring the decay of O2·− at 250 nm and the formation of ONOO at 302 nm to be (4.3 ± 0.5) × 109M−1s−1, independent of ionic strength and pH in the range of 6.1–10.0. The rate constant of the reaction of NO· with HO2·− was determined by following the decay of HO2· at 250 nm to be (3.2 ± 0.3) × 109 M−1s−1 at pH 3.3.