Liquid chromatography-tandem mass spectrometry assay for the quantification of free and total sialic acid in human cerebrospinal fluid

Research output: Contribution to journalArticle


Background: Analysis of sialic acid (SA) metabolites in cerebrospinal fluid (CSF) is important for clinical diagnosis. In the present study, a high-performance liquid chromatography-tandem mass spectrometry (HPLC/MS/MS) method for free sialic acid (FSA) and total sialic acid (TSA) in human CSF was validated. Methods: The method utilized a simple sample-preparation procedure of protein precipitation for FSA and acid hydrolysis for TSA. Negative electrospray ionisation was used to monitor the transitions m/z 308.2 → 87.0 (SA) and m/z 311.2 → 90.0 (13C3-SA). Conjugated sialic acid (CSA) was calculated by subtracting FSA from TSA. We established reference intervals for FSA, TSA and CSA in CSF in 217 control subjects. The method has been applied to patients' samples with known differences in SA metabolites like meningitis (n = 6), brain tumour (n = 2), leukaemia (n = 5), and Salla disease (n = 1). Results: Limit of detection (LOD) was 0.54 μM for FSA and 0.45 μM for TSA. Intra- and inter-assay variation for FSA (21.8 μM) were 4.8% (n = 10) and 10.4% (n = 40) respectively. Intra- and inter-assay variation for TSA (35.6 μM) were 9.7% (n = 10) and 12.8% (n = 40) respectively. Tested patients showed values of TSA above established reference value. Conclusion: The validated method allows sensitive and specific measurement of SA metabolites in CSF and can be applied for clinical diagnoses.


  • Maria van der Ham
  • Tom J. de Koning
  • Dirk Lefeber
  • André Fleer
  • Berthil H.C.M.T. Prinsen
  • Monique G.M. de Sain-van der Velden
External organisations
  • University Medical Center Utrecht
  • Radboud University Medical Center
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Neurosciences


  • Cerebrospinal fluid, High-performance liquid chromatography-tandem mass spectrometry, Sialic acid
Original languageEnglish
Pages (from-to)1098-1102
Number of pages5
JournalJournal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences
Issue number15-16
Publication statusPublished - 2010 May 1
Publication categoryResearch
Externally publishedYes