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Superoxide-dependent formation of hydroxyl radicals and lipid peroxidation in the presence of iron salts. Detection of 'catalytic' iron and anti-oxidant activity in extracellular fluids.

ABSTRACT: Synovial fluid from rheumatoid patients and normal cerebrospinal fluid contains micromolar concentrations of non-protein-bound iron salts that can promote lipid peroxidation and also the superoxide-dependent formation of hydroxyl radicals from hydrogen peroxide. These iron catalysts of oxygen radical reactions cannot be detected by conventional assays unless interfering high-molecular-weight substances, probably proteins, are removed by ultrafiltration or inactivated by exposure to low pH values. The bleomycin assay for ;catalytic' iron [Gutteridge, Rowley & Halliwell (1981) Biochem. J.199, 263-265] does not suffer from these artifacts.

SUBMITTER: Gutteridge JM

PROVIDER: S-EPMC1158629 | biostudies-other | 1982 Sep

REPOSITORIES: biostudies-other

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Superoxide-dependent formation of hydroxyl radicals in the presence of iron salts. Detection of 'free' iron in biological systems by using bleomycin-dependent degradation of DNA.

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