Highly selective acetone detector based on a separation channel and semiconductor gas sensor

Acetone is a biomarker of diabetics. The exhaled acetone concentration of diabetics is higher than that of a healthy person. Semiconductor gas sensors provide an accurate non-invasive detection method for low-concentration breath acetone of diabetics, but the their selectivity presents a drawback. In order to detect the concentration of exhaled acetone accurately from exhaled breath, an acetone detector based on a separation channel and semiconductor gas sensors is presented in this paper. Carbon dioxide, acetone, and ethanol were simulated and separated by a gas chromatography (GC) column in the separation channel. The separated time of carbon dioxide, exhaled acetone, and ethanol are 25 s, 236 s, and 574 s at room temperature, respectively. Carbon dioxide, acetone, and ethanol flow into three gas detection channels with the control of a time-sharing conversion switch. Then, carbon dioxide, acetone, and ethanol can be detected accurately by the semiconductor gas sensors. Exhaled acetone can be measured as low as 1 ppm within 5 min without any interference. A highly selective acetone detector based on GC and semiconductor technology has potential in monitoring and detecting diabetes as well as safe driving in a non-invasive way.