Virtual electronic nose with diagnosis model for the detection of hydrogen and methane in breath from gastrointestinal bacteria

Breath test is a prevalent detection method for gastrointestinal function, which is widely used on the diagnosis of carbohydrate malabsorption, and other gastrointestinal diseases. In this paper, a design of virtual electronic nose was presented to detect the concentration of hydrogen, methane and carbon dioxide in breath. The sample was pushed into chromatographic column for separation and every component was detected by one sensor. The concentration of hydrogen and methane were achieved after calibrated calculation, and can be corrected by carbon dioxide. The test results show that the detection range of hydrogen and methane is 1-500 ppm and the resolution is 1 ppm. The diagnosis model for small intestinal bacterial overgrowth was established and validated by local patients. This method has the advantages of high specificity, good repeatability, non-invasive, and simplicity of operation, so that can be used for the detection of increasing volume of clinical and domestic patients.