title: The direct determination of urinary oxalate by non-suppressed ion chromatography.
abstract: In this paper we describe a simple ion chromatographic method for determination of oxalate in urine. Acidified urine was diluted 1:2 with 0.03 mol/l benzidine hydrochloride in 0.3 mol/l boric acid to precipitate sulphate. The supernatant was passed through a C18-cartridge and 100 microliters of eluant were injected into an ion chromatographic system. Oxalate was measured by nonsuppressed conductivity detection. The detection limit for urinary oxalate was 0.05 mmol/l. The recovery for spiked urine samples was 101.5% with a CV of 4.5%. The within- and between-assay coefficients of variation were less than 4.5% and 2.5%, respectively. We found the results obtained by this method to be statistically equivalent to an enzymatic assay and a different ion-chromatographic method.
authors.affiliation: Forschungslabor der Klinik und Poliklinik für Urologie, Friedrich-Schiller-Universität Jena, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Pfeiffer
authors.forename: W
authors.initials: W
authors.lastname: Berg
authors.forename: D
authors.initials: D
authors.lastname: Bongartz
authors.forename: A
authors.initials: A
authors.lastname: Hesse
mesh_terms: D000704:Analysis of Variance; D002129:Calcium Oxalate / Q000652:urine; D002851:Chromatography, High Pressure Liquid / Q000379:methods* / Q000706:statistics & numerical data; D002852:Chromatography, Ion Exchange / Q000379:methods* / Q000706:statistics & numerical data; D005069:Evaluation Studies as Topic; D006801:Humans; D006863:Hydrogen-Ion Concentration; D010070:Oxalates / Q000652:urine*; D014545:Urinary Calculi / Q000175:diagnosis / Q000652:urine
chemical_list: D010070:Oxalates; D002129:Calcium Oxalate