CogniScent has developed a DNA-based sensing material that can detect, identify, and discriminate among a large number of airborne compounds in ~2 s. ScenTraK, a lightweight, handheld unit, uses an optoelectronic sensor array; its output drives software algorithms trained to ID specific olfactory patterns. It can detect target odors at the ppb and ppt levels, identify volatile compounds at a range of concentrations, and ignore background interferents. Neither sample preparation time nor special training is required; markets include security, medical, and industrial. (www.sensorsmag.com/0906/RDGas)