Stable isotope-dilution liquid chromatography/tandem mass spectrometry method for determination of thyroxine in saliva

J Chromatogr B Analyt Technol Biomed Life Sci. 2011 Apr 15;879(13-14):1013-7. doi: 10.1016/j.jchromb.2011.02.048. Epub 2011 Mar 23.

Abstract

A liquid chromatography/electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS) method for the determination of thyroxine (T(4)) in human saliva has been developed and validated. The saliva was deproteinized with methanol, purified using a Strata-X™ cartridge, and subjected to LC/ESI-MS/MS. Quantification was based on selected reaction monitoring, and [(13)C(6)]-T(4) was used as the internal standard. This method allowed the reproducible (intra- and inter-assay relative standard deviations, <4.8%) and accurate (analytical recovery, 96.5-99.6%) quantification of the salivary T(4) using a 400 μl sample, and the limit of quantification was 25.0 pg/ml. A preliminary study using the developed method found that there is a diagnosable difference in the salivary T(4) concentration between the euthyroid subjects and the patients with Graves disease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Drug Stability
  • Female
  • Graves Disease / metabolism
  • Humans
  • Isotope Labeling / methods*
  • Linear Models
  • Male
  • Reproducibility of Results
  • Saliva / chemistry*
  • Sensitivity and Specificity
  • Tandem Mass Spectrometry / methods*
  • Thyroxine / analysis*
  • Thyroxine / chemistry

Substances

  • Thyroxine