Photoacoustic Spectroscopy-Based Breath Analysis for SIBO

Breath hydrogen (H₂) and methane (CH₄) monitoring play an important role in the diagnosis of gastrointestinal disorders, such as lactose intolerance and small intestinal bacterial overgrowth (SIBO). In this paper, the photoacoustic spectroscopy method is used for H₂ gas and CH₄ gas detection. We present a novel approach for H₂ gas concentration measurement, which is the linear relationship between the resonant frequency of breath carbon dioxide (CO₂) and the H₂ concentration in a resonant photoacoustic cell. Experimental results show that the minimum detectable limits of H₂, CH₄, and CO₂ are calculated to be 8.86, 0.56, and 145.14 ppm, respectively, which can meet the requirements of breath diagnosis.