Photoacoustic Spectroscopy-Based Breath Analysis for SIBO

Breath hydrogen (H 2 ) and methane (CH 4 ) 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 H 2 gas and CH 4 gas detection. We present a novel approach for H 2 gas concentration measurement, which is the linear relationship between the resonant frequency of breath carbon dioxide (CO 2 ) and the H 2 concentration in a resonant photoacoustic cell. Experimental results show that the minimum detectable limits of H 2, CH 4, and CO 2 are calculated to be 8.86, 0.56, and 145.14 ppm, respectively, which can meet the requirements of breath diagnosis.