Determination of copper in urine and serum by gas chromatography-mass spectrometry.
A stable isotope dilution gas chromatography-mass spectrometry method using enriched 65Cu as an internal standard is described for the determination of Cu in urine and serum. Chelating agents N,N'-ethylenebis-(trifluoroacetylacetoneimine) [H2(enTFA2)] and lithium bis(trifluoroethyl)dithiocarbamate [Li(FDEDTC)] were used and evaluated for memory effect. H2(enTFA2) did not show any appreciable memory effect, whereas Li(FDEDTC) was found to have a strong memory effect. Overall precision of 1.6% was obtained for determining Cu isotope ratios at a 10-ng level using H2(enTFA2). Cu concentrations in the National Institute of Standards and Technology (NIST) reference materials, freeze-dried urine SRM 2670, and human serum SRM 909 determined using the H2(enTFA2) chelating agent were in good agreement with the NIST-certified values. Isotope ratios determined by gas chromatography-mass spectrometry on samples with altered isotopic composition were in good agreement with the inductively coupled plasma-mass spectrometry data.
Aggarwal
S K
SK
Department of Pathology, University of Virginia Health Sciences Center, Charlottesville 22908.
Kinter
M
M
Herold
D A
DA
D002614:Chelating Agents; D003300:Copper / Q000032:analysis* / Q000097:blood / Q000652:urine; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007097:Imines; D007554:Isotopes; D008832:Microchemistry / Q000379:methods; D010422:Pentanones; D012015:Reference Standards; D013859:Thiocarbamates
D002614:Chelating Agents; D007097:Imines; D007554:Isotopes; D010422:Pentanones; D013859:Thiocarbamates; C063247:bis(trifluoroethyl)carbamodithioic acid; C070206:N,N'-ethylenebis(trifluoroacetylacetoneimine); D003300:Copper