SpectrophotometricDeterminationof UrinaryOxalatewith OxalateOxidase
نویسندگان
چکیده
A novel spectrophotometric enzymlc procedure for estimating oxalic acid in urine is described. Oxalate oxidase, prepared from moss species, converts oxalic acid to hydrogen peroxide and carbon dioxide. Hydrogen peroxide is determined enzymatically with horseradish peroxidase, by oxidative coupling of 3-methyl-2-benzothiazolinone hydrazone with N,N-dimethylaniline; the resulting indamine dye is determined spectrophotometrically at 595 nm. Interfering substances are removed by adsorption to ionexchange resins and oxidation with charcoal, thus avoiding oxalate recovery problems accompanying oxalate isolation. The procedure is rapid, sensitive, linear, and precise. Results agreed well with those obtained with a widely used chemical technique.
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