title: The analysis of thyroxine in human serum by an 'exact matching' isotope dilution method with liquid chromatography/tandem mass spectrometry.
abstract: A method for the analysis of thyroxine in human serum, utilising 'exact matching' isotope dilution mass spectrometry (IDMS) in combination with liquid chromatography/tandem mass spectrometry (LC/MS/MS), has been developed with a limit of quantification of 0.5 ng g(-1) of thyroxine in human serum. The extraction and clean-up of thyroxine from serum involves an efficient protein-precipitation stage followed by a solid-phase extraction procedure to produce an extract essentially free from interfering compounds. The method is reproducible, with expanded uncertainties of less than 2%, and is relatively fast to perform.
authors.affiliation: Laboratory of the Government Chemist (LGC Limited), Queens Road, Teddington, Middlesex TW11 0LY, UK.
authors.forename: Chris J
authors.initials: CJ
authors.lastname: Hopley
authors.forename: Peter
authors.initials: P
authors.lastname: Stokes
authors.forename: Kenneth S
authors.initials: KS
authors.lastname: Webb
authors.forename: Michael
authors.initials: M
authors.lastname: Baynham
mesh_terms: D001774:Blood Chemical Analysis / Q000379:methods; D002247:Carbon Isotopes; D002853:Chromatography, Liquid / Q000379:methods; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods*; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D013974:Thyroxine / Q000097:blood*
chemical_list: D002247:Carbon Isotopes; D013974:Thyroxine