Human breath analysis: methods for sample collection and reduction of localized background effects

Area of Science:

• Analytical Chemistry
• Environmental Science

Background:

• Analysis of volatile organic compounds (VOCs) in human breath is crucial for diagnostics and environmental monitoring.
• Traditional methods often require cumbersome sample collection, such as exhaled breath condensate, and can be time-consuming.
• Existing techniques may struggle with portability and performance in contaminated environments.

Purpose of the Study:

• To introduce and evaluate a new method for direct analysis of VOCs in exhaled breath vapor (EBV) using active solid-phase microextraction (SPME).
• To compare the novel EBV collection method with traditional exhaled breath condensate collection.
• To demonstrate the importance of clean inhaled air for accurate breath sample analysis.

Main Methods:

• Development of an exhaled breath vapor (EBV) collection procedure using active SPME with a modified breath-collection device (RTube).
• Direct desorption of analytes from the SPME fiber into a gas chromatography-mass spectrometry (GC-MS) system.
• Comparison of EBV collection at different temperatures and with traditional condensate collection.
• Demonstration of contaminant sources and methods for providing clean inhaled air.

Main Results:

• The active SPME EBV method provides faster sample collection and data analysis compared to traditional methods.
• The apparatus is portable and does not require power or cooling, enhancing ease-of-use.
• The method effectively minimizes background contaminants, allowing for facile data interpretation, even in contaminated environments.

Conclusions:

• Active SPME EBV collection is a superior alternative for analyzing VOCs in human breath.
• This technique offers significant advantages in speed, portability, and performance, especially in challenging environments.
• Ensuring clean inhaled air is critical for reliable breath sample analysis.