ArticleChemistry Central journal2016
Freeze-drying: an alternative method for the analysis of volatile organic compounds in the headspace of urine samples using solid phase micro-extraction coupled to gas chromatography - mass spectrometry.
Article in Chemistry Central journal, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 15 papers.
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15 citing papers in PubMed, 39 citations in OpenAlex.
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- Untargeted Plant Metabolomics: Evaluation of Lyophilization as a Sample Preparation Technique.Metabolites · 2023Article
- A Complete Pipeline for Untargeted Urinary Volatolomic Profiling with Sorptive Extraction and Dual Polar and Nonpolar Column Methodologies Coupled with Gas Chromatography Time-of-Flight Mass Spectrometry.Analytical chemistry · 2023Article
- GC-MS Techniques Investigating Potential Biomarkers of Dying in the Last Weeks with Lung Cancer.International journal of molecular sciences · 2023Article
- The untargeted urine volatilome for biomedical applications: methodology and volatilome database.Biological procedures online · 2022Review
- Mapping of Urinary Volatile Organic Compounds by a Rapid Analytical Method Using Gas Chromatography Coupled to Ion Mobility Spectrometry (GC-IMS).Metabolites · 2022Article
- Evaluation of fresh, frozen, and lyophilized fecal samples by SPME and derivatization methods using GC×GC-TOFMS.Metabolomics : Official journal of the Metabolomic Society · 2022Article
- Optimising storage conditions and processing of sheep urine for nitrogen cycle and gaseous emission measurements from urine patches.Scientific reports · 2021Article
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- An Optimization of Liquid-Liquid Extraction of Urinary Volatile and Semi-Volatile Compounds and Its Application for Gas Chromatography-Mass Spectrometry and Proton Nuclear Magnetic Resonance Spectroscopy.Molecules (Basel, Switzerland) · 2020Article
- Sniffing Out Urinary Tract Infection-Diagnosis Based on Volatile Organic Compounds and Smell Profile.Biosensors · 2020Review
- A targeted metabolomic protocol for quantitative analysis of volatile organic compounds in urine of children with celiac disease.RSC advances · 2018Article
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7 authors at 2 institutions in 1 country.
Funding
Abstract
backgroundVolatile organic compounds (VOCs) can be intermediates of metabolic pathways and their levels in biological samples may provide a better understanding about diseases in addition to potential methods for diagnosis. Headspace analysis of VOCs in urine samples using solid phase micro extraction (SPME) coupled to gas chromatography - mass spectrometry (GC-MS) is one of the most used techniques. However, it generally produces a limited profile of VOCs if applied to fresh urine. Sample preparation methods, such as addition of salt, base or acid, have been developed to improve the headspace-SPME-GC-MS analysis of VOCs in urine samples. These methods result in a richer profile of VOCs, however, they may also add potential contaminants to the urine samples, result in increased variability introduced by manually processing the samples and promote degradation of metabolites due to extreme pH levels. Here, we evaluated if freeze-drying can be considered an alternative sample preparation method for headspace-SPME-GC-MS analysis of urine samples.
resultsWe collected urine from three volunteers and compared the performances of freeze-drying, addition of acid (HCl), addition of base (NaOH), addition of salt (NaCl), fresh urine and frozen urine when identifying and quantifying metabolites in 4 ml samples. Freeze-drying and addition of acid produced a significantly higher number of VOCs identified than any other method, with freeze-drying covering a slightly higher number of chemical classes, showing an improved repeatability and reducing siloxane impurities.
conclusionIn this work we compared the performance of sample preparation methods for the SPME-GC-MS analysis of urine samples. To the best of our knowledge, this is the first study evaluating the potential of freeze-dry as an alternative sample preparation method. Our results indicate that freeze-drying has potential to be used as an alternative method for the SPME-GC-MS analysis of urine samples. Additional studies using internal standard, synthetic urine and calibration curves will allow a more precise quantification of metabolites and additional comparisons between methods.Graphical abstractEnhancing VOC profiling from urine samples.
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