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An improved high performance liquid chromatographic method for determining urinary oxalate, making use of an ID-MS reference method.

W Koolstra·B G Wolthers·M Hayer·H M Rutgers
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Abstract

With the aid of a newly developed isotope dilution mass spectrometric (ID-MS) measurement of urinary oxalate, an existing HPLC method for assaying this substance was investigated. Results obtained with this method were too high, apparently due to a systematic error. Subsequently, this method was improved by additional prepurification in three different ways: (a) precipitation with CaSO4 to Ca-oxalate, (b) adsorption (and subsequent desorption) to columns supplied with a commercial kit for urinary oxalate and (c) the enzymatic destruction of urinary oxalate present. This work demonstrates the successful use of a reference method in improving a newly developed analytical procedure and presents a reliable and reproducible HPLC method for determining urinary oxalate.

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Chromatography, High Pressure LiquidGas Chromatography-Mass SpectrometryHumansOxalatesOxalic AcidReference StandardsJournal Article

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W Koolstra, B G Wolthers, M Hayer, H M Rutgers. 1987. An improved high performance liquid chromatographic method for determining urinary oxalate, making use of an ID-MS reference method.. https://doi.org/10.1016/0009-8981(87)90133-1

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