Gas-Sensing Technology for Human Breath Detection

Changes in volatile organic compounds concentrations in human breath are closely related to certain diseases, and the diagnosis of diseases by analyzing volatile organic compounds in human breath is a non-invasive, and easy-to-use tool that has received increasing attention in recent years for applications in disease diagnosis and early screening. There are currently two main types of equipment for detecting volatile organic compounds in exhaled breath: mass spectrometry-based analytical instruments and gas-sensitive sensors. With easy integration, miniaturization, low cost, and simple operation, gas-sensitive sensors have broad application prospects in the future diagnosis and early screening of large-scale population diseases. This review systematically describes the working mechanism of gas sensors, sensor performance, the current status of application of different sensitive materials and the application of different gas sensor types in human breath detection, the types of volatile organic compounds in human breath that are associated with some diseases are also introduced, which is followed by a brief introduction to the means of breath sampling and the data processing methods currently in use. Finally, the problems of current gas sensor technology in breath detection are pointed out, and the prospects of gas sensor technology in human breath detection are foreseen.