Development of non-invasive breath analyzer : A proposed system for detection of Nitric oxide (NO) in exhaled human breath, using infrared Quantum Cascade Laser (QCL) absorption technique

The detection and monitoring of gases in exhaled human breath till date has been limited by the lack of appropriate materials and technologies which could rapidly and selectively identify the presence and monitor the concentration of trace levels of specific biomarkers. In this paper, a method for detection of NO in exhaled breath has been proposed. Development of a continuous wave, thermoelectrically cooled, Distributed Feedback Quantum Cascade Laser (DFB-QCL) based sensor platform operating near 5.26 μm, in combination with QEPAS has been proposed for the quantitative detection of exhaled NO concentrations, which is a biomarker of airway inflammation and can indicate the extent of respiratory diseases.