Real-Time Measurement of CH4 in Human Breath Using a Compact CH4/CO2 Sensor

• DOI: 10.3390/s24041077
• Publication Date: 2024-02-07T08:47:09Z
• Authors: Yueyu Lin; Dexter Manalili; Amir Khodabakhsh; Simona M. Cristescu
• Keywords: Breath gas analysis; Carbon dioxide sensor; Exhaled air; Respiratory monitoring

The presence of an elevated amount methane (CH4) in exhaled breath can be used as a non-invasive tool to monitor certain health conditions. A compact, inexpensive and transportable CH4 sensor is thus very interesting for this purpose. In addition, if the also able simultaneously measure carbon dioxide (CO2), one extract end-tidal concentration CH4. Here, we report on such based commercial detection module using tunable diode laser absorption spectroscopy. It was found that measured CH4/CO2 values exhibit strong interference with water vapor. Therefore, correction functions were experimentally identified validated both CO2 custom-built sampler developed tested real-time measurements breath. As result, demonstrated capability accurately measuring profiles real-time. We obtained minimum limits ~80 ppbv ~700 ppmv 1.5 s measurement time.