Mass spectrometric quantification of urinary 6-sulfatoxymelatonin: age-dependent excretion and biological variation

Martijn van Faassen, Anna van der Veen, Sonja van Ockenburg, Helma de Jong, Elisabeth G E de Vries, Ido P Kema*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

1 Citation (Scopus)
2 Downloads (Pure)

Abstract

Objectives: Regulators of circadian rhythm, including melatonin, influence fundamental biological processes. Measuring the melatonin metabolite 6-sulfatoxymelatonin in urine can estimate melatonin production. 6-sulfatoxymelatonin is mainly analyzed by immunoassays, but these methods are hampered by cross-reactivity and poor reproducibility when used to analyze small molecules. Therefore, we validated a high-throughput liquid chromatography with tandem mass spectrometry (LC-MS/MS) method to quantify 6-sulfatoxymelatonin in urine. We evaluated age-dependent 24-h excretion of 6-sulfatoxymelatonin into urine and the biological variation of urinary excretion in healthy individuals.

Methods: The online solid phase extraction method combined with LC-MS/MS was validated according to international guidelines, and used to measure the excretion of 6-sulfatoxymelatonin into urine of 240 healthy individuals. Biological variation of 6-sulfatoxymelatonin excretion was examined in 10 healthy individuals.

Results: Urinary 6-sulfatoxymelatonin results were well within the validation criteria (interassay coefficient of variation:

Conclusions: This MS-based method enables straightforward, reproducible, and sensitive quantification of 6-sulfatoxymelatonin in urine. Urinary 6-sulfatoxymelatonin levels decreased with age. Biological variation of 6-sulfatoxymelatonin excretion into urine was high between subjects and lower within subjects, indicating that repeated measurements of 6-sulfatoxymelatonin in 24-h urine are needed in future studies.

Original languageEnglish
Pages (from-to)187-195
Number of pages9
JournalClinical chemistry and laboratory medicine
Volume59
Issue number1
Early online date16-Jul-2020
DOIs
Publication statusPublished - 1-Jan-2021

Keywords

  • biological variation
  • melatonin
  • tandem mass spectrometry
  • 6-sulfatoxymelatonin
  • urine
  • 6-HYDROXYMELATONIN SULFATE
  • MELATONIN SECRETION
  • SLEEP DISRUPTION
  • CIRCADIAN-RHYTHM
  • RISK
  • IMMUNOASSAY
  • CANCER
  • RATES

Cite this