Fully automated solid-phase microextraction–fast gas chromatography–mass spectrometry method using a new ionic liquid column for high-throughput analysis of sarcosine and N-ethylglycine in human urine and urinary sediments

• Published in: Analytica chimica acta Vol. 707; no. 1; pp. 197 - 203
• Main Authors: Bianchi, F., Dugheri, S., Musci, M., Bonacchi, A., Salvadori, E., Arcangeli, G., Cupelli, V., Lanciotti, M., Masieri, L., Serni, S., Carini, M., Careri, M., Mangia, A.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 30.11.2011; Elsevier
• Subjects: Analytical chemistry; automation; Biological and medical sciences; biomarkers; Cancer; Cell physiology; Cell transformation and carcinogenesis. Action of oncogenes and antioncogenes; Chemistry; Chromatographic methods and physical methods associated with chromatography; creatinine; Cut-off; derivatization; Exact sciences and technology; Fast GC; Fundamental and applied biological sciences. Psychology; Gas chromatographic methods; gas chromatography-mass spectrometry; Gas Chromatography-Mass Spectrometry - methods; Humans; hypertrophy; Ionic liquid column; Ionic liquids; Ionic Liquids - analysis; Ionic Liquids - chemistry; Male; Molecular and cellular biology; N-substituted Glycines - urine; Patients; Prostate; Prostate cancer; prostatic neoplasms; Sarcosine; Sarcosine - urine; Sediments; Solid Phase Microextraction - methods; Solid-phase microextraction; Spectrometric and optical methods; Spectroscopy; Time Factors; Urine; Solid-phase microextraction; Fast GC; Ionic liquid column; Prostate cancer; Sarcosine; Solid phase extraction; Biological marker; Liquid column; Gas analysis; Derivatization; Robotics; Ionic liquid; Direct method; Apparatus; Time analysis; Quantitative analysis; Trace analysis; Human; Urine; Automation; Sample; Use; Sediments; Automatic processing; Solid phase microextraction; Gas chromatography; Non destructive method; Repeatability; Sensitivity; Preparation; Limit; Miniaturization; Detection; Prostate; Mass spectrometry
• ISSN: 0003-2670; 1873-4324; 1873-4324
• DOI: 10.1016/j.aca.2011.09.015

[Display omitted] ► Fully automated SPME–Fast GC–MS method for sarcosine and N-ethylglycine determination. ► Possibility of high-throughput analyses and point of care testing. ► Potential role of sarcosine as biomarker for prostate cancer detection. A fully automated, non invasive, rapid and high-throughput method for the direct determination of sarcosine and N-ethylglycine in urine and urinary sediments using hexyl chloroformate derivatization followed by direct immersion solid-phase micro extraction and fast gas chromatography–mass spectrometric analysis was developed and validated. The use of a new ionic liquid narrow bore column, as well as the automation and miniaturization of the preparation procedure by a customized configuration of the utilized XYZ robotic system, allowed a friendly use of the GC apparatus achieving a quantitation limit of 0.06 μg L −1 for sarcosine, good repeatability with CV always lower than 7% and reduced analysis times useful for point-of-care testing. The method was then applied for the analysis of 56 samples of urine and urinary sediments in healthy subjects, in those with benign prostatic hypertrophy and in patients with clinically localized prostate cancer. The results obtained showed that the medians of sarcosine/creatinine in urine were 103, 137 and 267 μg g −1 respectively, thus assessing the potential use of sarcosine as urinary biomarker for prostate cancer detection. The highest values of sensitivity (79%) and specificity (87%) were obtained in correspondence of a cut-off value of 179 μg sarcosine (g creatinine) −1, thus by using this cut-off threshold, sarcosine was significantly associated with the presence of cancer ( p < 0.0001). Finally, ROC analyses proved that the discrimination between clinically localized prostate cancer and patients without evidence of tumor is significantly correlated with sarcosine.