Title: | Gas chromatographic-mass spectrometric analysis of urinary volatile organic metabolites: Optimization of the HS-SPME procedure and sample storage conditions |
Author(s): | Zivkovic Semren T; Brcic Karaconji I; Safner T; Brajenovic N; Tariba Lovakovic B; Pizent A; |
Address: | "Analytical Toxicology and Mineral Metabolism Unit, Institute for Medical Research and Occupational Health, Ksaverska c. 2, HR-10001 Zagreb, Croatia. Department of Plant Breeding Genetics, Biometrics and Experimentation, University of Zagreb, Faculty of Agriculture, Svetosimunska cesta 25, HR-10000 Zagreb, Croatia. Analytical Toxicology and Mineral Metabolism Unit, Institute for Medical Research and Occupational Health, Ksaverska c. 2, HR-10001 Zagreb, Croatia. Electronic address: btariba@imi.hr" |
DOI: | 10.1016/j.talanta.2017.08.064 |
ISSN/ISBN: | 1873-3573 (Electronic) 0039-9140 (Linking) |
Abstract: | "Non-targeted metabolomics research of human volatile urinary metabolome can be used to identify potential biomarkers associated with the changes in metabolism related to various health disorders. To ensure reliable analysis of urinary volatile organic metabolites (VOMs) by gas chromatography-mass spectrometry (GC-MS), parameters affecting the headspace-solid phase microextraction (HS-SPME) procedure have been evaluated and optimized. The influence of incubation and extraction temperatures and times, coating fibre material and salt addition on SPME efficiency was investigated by multivariate optimization methods using reduced factorial and Doehlert matrix designs. The results showed optimum values for temperature to be 60 degrees C, extraction time 50min, and incubation time 35min. The proposed conditions were applied to investigate urine samples' stability regarding different storage conditions and freeze-thaw processes. The sum of peak areas of urine samples stored at 4 degrees C, -20 degrees C, and -80 degrees C up to six months showed a time dependent decrease over time although storage at -80 degrees C resulted in a slight non-significant reduction comparing to the fresh sample. However, due to the volatile nature of the analysed compounds, more than two cycles of freezing/thawing of the sample stored for six months at -80 degrees C should be avoided whenever possible" |
Keywords: | Adult Gas Chromatography-Mass Spectrometry Humans Male Metabolome Solid Phase Microextraction/*methods Specimen Handling Temperature Volatile Organic Compounds/*urine HS-SPME procedure Metabolomic Sample stability Urine samples Volatile organic metabolite; |
Notes: | "MedlineZivkovic Semren, Tanja Brcic Karaconji, Irena Safner, Toni Brajenovic, Natasa Tariba Lovakovic, Blanka Pizent, Alica eng Netherlands 2017/09/18 Talanta. 2018 Jan 1; 176:537-543. doi: 10.1016/j.talanta.2017.08.064. Epub 2017 Aug 29" |