Non-invasive breath collection in murine models using a newly developed sampling device

Area of Science:

• Biomarkers and Disease Research
• Animal Models in Medical Science
• Analytical Chemistry and Mass Spectrometry

Background:

• Volatile organic compounds (VOCs) in exhaled breath show promise as disease biomarkers.
• Clinical studies are challenged by factors affecting breath VOC composition.
• Animal models offer insights but often require invasive or terminal breath collection.

Purpose of the Study:

• To develop and validate a novel, non-invasive device for breath collection in mice.
• To assess the reproducibility of volatile organic compound (VOC) measurements using this device.
• To optimize air sampling parameters for reliable breath VOC analysis in murine models.

Main Methods:

• A non-invasive breath collection device using glass nose-only restrainers was designed for mice.
• Exhaled air was collected on desorption tubes and analyzed using gas chromatography time-of-flight mass spectrometry (GC-tof-MS).
• Reproducibility was tested by varying airflow (ml/min) and collection time (minutes) in C57Bl/6 J mice.

Main Results:

• Twenty-seven VOC compounds were putatively identified in mouse breath.
• Optimal reproducibility was achieved with an airflow of 185 ml/min and a 20-minute collection time.
• The non-invasive method demonstrated good potential for VOC analysis in research settings.

Conclusions:

• The developed device enables non-invasive, reproducible breath VOC collection in mice.
• This method facilitates long-term studies of metabolic disturbances and disease pathways in animal models.
• It overcomes limitations of traditional invasive breath collection techniques in preclinical research.