| Title: | "Optimisation of Urine Sample Preparation for Headspace-Solid Phase Microextraction Gas Chromatography-Mass Spectrometry: Altering Sample pH, Sulphuric Acid Concentration and Phase Ratio" |
| Author(s): | Aggarwal P; Baker J; Boyd MT; Coyle S; Probert C; Chapman EA; |
| Address: | "Department of Molecular and Clinical Cancer Medicine, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 3BX, UK. School of Medicine, Cedar House, University of Liverpool, Liverpool L69 3GE, UK. Department of Molecular and Clinical Cancer Medicine, Institute of Systems, Molecular and Integrative Biology, Cancer Research Centre, University of Liverpool, Liverpool L3 9TA, UK. Palliative Care Institute Liverpool, Cancer Research Centre, University of Liverpool, Liverpool L3 9TA, UK. Clatterbridge Cancer Centre, Liverpool L7 8YA, UK. School of Medical Sciences, Bangor University, Bangor, Gwynedd LL57 2DG, UK" |
| ISSN/ISBN: | 2218-1989 (Print) 2218-1989 (Electronic) 2218-1989 (Linking) |
| Abstract: | "Headspace-solid phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) can be used to measure volatile organic compounds (VOCs) in human urine. However, there is no widely adopted standardised protocol for the preparation of urine samples for analysis resulting in an inability to compare studies reliably between laboratories. This paper investigated the effect of altering urine sample pH, volume, and vial size for optimising detection of VOCs when using HS-SPME-GC-MS. This is the first, direct comparison of H(2)SO(4), HCl, and NaOH as treatment techniques prior to HS-SPME-GC-MS analysis. Altering urine sample pH indicates that H(2)SO(4) is more effective at optimising detection of VOCs than HCl or NaOH. H(2)SO(4) resulted in a significantly larger mean number of VOCs being identified per sample (on average, 33.5 VOCs to 24.3 in HCl or 12.2 in NaOH treated urine) and more unique VOCs, produced a more diverse range of classes of VOCs, and led to less HS-SPME-GC-MS degradation. We propose that adding 0.2 mL of 2.5 M H(2)SO(4) to 1 mL of urine within a 10 mL headspace vial is the optimal sample preparation prior to HS-SPME-GC-MS analysis. We hope the use of our optimised method for urinary HS-SPME-GC-MS analysis will enhance our understanding of human disease and bolster metabolic biomarker identification" |
| Keywords: | H2so4 HCl Hs-spme-gc-ms NaOH VOCs hydrochloric acid sodium hydroxide vials volatile organic compounds; |
| Notes: | "PubMed-not-MEDLINEAggarwal, Prashant Baker, James Boyd, Mark T Coyle, Seamus Probert, Chris Chapman, Elinor A eng 202022/Z/16/Z/WT_/Wellcome Trust/United Kingdom SI2018.11/North West Cancer Research Fund/ intercalation award/Wolfson Foundation/ MRes bursary/North West Cancer Research Fund/ Switzerland 2020/12/02 Metabolites. 2020 Nov 25; 10(12):482. doi: 10.3390/metabo10120482" |
