Automated mass spectrometric analysis of urinary and plasma serotonin

• Published in: Analytical and bioanalytical chemistry Vol. 396; no. 7; pp. 2609 - 2616
• Main Authors: de Jong, Wilhelmina H. A, Wilkens, Marianne H. L. I, de Vries, Elisabeth G. E, Kema, Ido P
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Berlin/Heidelberg : Springer-Verlag 01.04.2010; Springer-Verlag; Springer
• Subjects: Algorithms; Analysis; Analytical Chemistry; Automated; Biochemistry; Biological and medical sciences; Blood Chemical Analysis - methods; Blood plasma; bone formation; Carcinoid; cation exchange; Cell physiology; Cell transformation and carcinogenesis. Action of oncogenes and antioncogenes; Characterization and Evaluation of Materials; Chemical properties; Chemistry; Chemistry and Materials Science; Chromatographic methods and physical methods associated with chromatography; Chromatography, High Pressure Liquid - methods; creatinine; Exact sciences and technology; Extraction (Chemistry); Food Science; Fundamental and applied biological sciences. Psychology; Health aspects; hepatocytes; High performance liquid chromatography; Humans; hydrophilic interaction chromatography; ionization; Laboratory Medicine; Mass spectrometry; Mathematical analysis; metastasis; Methods; Molecular and cellular biology; monitoring; Monitoring/Environmental Analysis; neoplasms; Original Paper; Other chromatographic methods; patients; Physiological aspects; Reproducibility of Results; Robotics - methods; Sensitivity and Specificity; Serotonin; Serotonin - blood; Serotonin - urine; Serotonin metabolism; solid phase extraction; Solid Phase Extraction - methods; spectrometers; Spectrometric and optical methods; Spectrometry, Mass, Electrospray Ionization - methods; Spectroscopy; tandem mass spectrometry; Urinalysis - methods; Urine; Netherlands; On-line SPE; LC-MS/MS; Automation; Serotonin; 5-hydroxytryptamine; Mass spectrometry; Solid phase extraction; Plasma; Chemical analysis; Internal standard; Liver; HPLC chromatography; Time; Electrospray; Quadrupole spectrometer; Detection limit; Production; Tumor; Monitoring; Cation exchange; Human; Hormone; Urine; Coupled method; Concentration; Calibration; Chemical ionization; Automatic processing; Platelet; Linearity; Mass spectrometry MS/MS; Automatic analysis; Detection
• ISSN: 1618-2642; 1618-2650; 1618-2650
• DOI: 10.1007/s00216-010-3466-5

Serotonin emerges as crucial neurotransmitter and hormone in a growing number of different physiologic processes. Besides extensive serotonin production previously noted in patients with metastatic carcinoid tumors, serotonin now is implicated in liver cell regeneration and bone formation. The aim was to develop a rapid, sensitive, and highly selective automated on-line solid-phase extraction method coupled to high-performance liquid chromatography-tandem mass spectrometry (XLC-MS/MS) to quantify low serotonin concentrations in matrices such as platelet-poor plasma and urine. Fifty microliters plasma or 2.5 μL urine equivalent were pre-purified by automated on-line solid-phase extraction, using weak cation exchange. Chromatography of serotonin and its deuterated internal standard was performed with hydrophilic interaction chromatography. Mass spectrometric detection was operated in multiple reaction monitoring mode using a quadrupole tandem mass spectrometer with positive electrospray ionization. Serotonin concentrations were determined in platelet-poor plasma of metastatic carcinoid patients (n = 23) and healthy controls (n = 22). Urinary reference intervals were set by analyzing 24-h urine collections of 120 healthy subjects. Total run-time was 6 min. Intra- and inter-assay analytical variation were <10%. Linearity in the 0-7300 μmol/L calibration range was excellent (R² > 0.99). Quantification limits were 30 and 0.9 nmol/L in urine and plasma, respectively. Platelet-poor serotonin concentrations in metastatic carcinoid patients were significantly higher than in controls. The urinary reference interval was 10-78 μmol/mol creatinine. Serotonin analysis with sensitive and specific XLC-MS/MS overcomes limitations of conventional HPLC. This enables accurate quantification of serotonin for both routine diagnostic procedures and research in serotonin-related disorders.