Current status of midinfrared quantum and interband cascade lasers for clinical breath analysis

State-of-the-art quantum- and interband-cascade-based chemical sensors may be effective new tools for the identification and quantification of trace gases in human breath for clinical uses. Increased or decreased concentrations of these molecules are associated with the pathogenesis of a large number of diseases. Current technologies enable breath analyses to be performed on a single breath and the results are available in real time. Critical parameters including sensor sensitivity, selectivity, real-time monitoring capability, robustness, cost, size, and weight determine the progress made toward the development and availability of commercial diagnostic material.