title: Determination of chromium in urine by stable isotope dilution gas chromatography/mass spectrometry using lithium bis(trifluoroethyl)dithiocarbamate as a chelating agent.
abstract: An isotope dilution gas chromatography/mass spectrometry method using lithium bis(trifluoroethyl)dithiocarbamate as a chelating agent is described for the determination of chromium in urine. A wet digestion procedure with HNO3-H2O2 is used for oxidizing the organic matter associated with urine samples. The isotope ratios are measured by selected ion monitoring in a general-purpose mass spectrometer using a 10-m fused silica capillary column. Memory effect, in sequential analyses of samples with different isotope ratios, was evaluated by preparing a series of synthetic mixtures and was found to be negligible. The accuracy of the method was verified by quantitation of chromium in the NIST freeze-dried urine reference material, SRM-2670, with a recommended chromium concentration of 13 micrograms/L in the normal level and certified chromium concentration of 85 +/- 6 micrograms/L in the elevated level.
authors.affiliation: Department of Pathology, University of Virginia Health Sciences Center, Charlottesville 22908.
authors.forename: S K
authors.initials: SK
authors.lastname: Aggarwal
authors.forename: M
authors.initials: M
authors.lastname: Kinter
authors.forename: M R
authors.initials: MR
authors.lastname: Wills
authors.forename: J
authors.initials: J
authors.lastname: Savory
authors.forename: D A
authors.initials: DA
authors.lastname: Herold
mesh_terms: D002614:Chelating Agents; D002857:Chromium / Q000652:urine*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D011865:Radioisotope Dilution Technique; D013859:Thiocarbamates
chemical_list: D002614:Chelating Agents; D013859:Thiocarbamates; D002857:Chromium; C063247:bis(trifluoroethyl)carbamodithioic acid