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A Microfluidic Model of Biomimetically Breathing Pulmonary Acinar Airways
Published on: May 9, 2016
Differences between alveolar air and mouth air.
Sandra van den Velde1, Marc Quirynen, Paul van Hee
1Department of Periodontology, University of Leuven, Kapucijnenvoer 7, 3000 Leuven, Belgium.
Analytical Chemistry
|March 24, 2007
Summary
Breath analysis reveals significant differences between mouth and alveolar air composition in healthy individuals. Gas chromatography-mass spectrometry identified distinct metabolic compounds in lung air versus oropharyngeal air.
Area of Science:
- Analytical Chemistry
- Respiratory Physiology
- Metabolomics
Background:
- Breath contains distinct intraoral (mouth) and alveolar (lung) components.
- Alveolar air, exhaled last, is expected to contain more metabolic compounds from blood-air exchange.
Purpose of the Study:
- To investigate the chemical composition differences between oropharyngeal and alveolar breath in healthy volunteers.
- To characterize the volatile organic compounds present in different parts of exhaled breath.
Main Methods:
- Analysis of mouth air, alveolar air, and room air from 40 healthy volunteers.
- Utilized gas chromatography-mass spectrometry (GC-MS) for compound identification and quantification.
Main Results:
- An average of 145 compounds per chromatogram, with 618 compounds detected in total.
- Significantly higher number of compounds detected in mouth air compared to alveolar air.
- 47 compounds showed significant differences in detection or concentration between the two breath types.
Conclusions:
- Gas chromatography-mass spectrometry provides a detailed profile of breath composition.
- A clear distinction exists in chemical profiles between alveolar and oropharyngeal air, highlighting the importance of sampling location in breath analysis.
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