Sun originally began working on gas-sensing technology to help find illegal drugs and explosives—a job often left to dogs with specialized training.
"Those are trained sniffer dogs, and they can do the job by just simply smelling," Sun says. "So I thought, 'why can't we engineers design something like an electronic sensor that can beat that?'"
In more recent years, Sun and his colleagues have been working on other devices to sense airborne molecules and use them as biomarkers to screen for medical conditions such as Alzheimer's disease and lung cancer.
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( why not use trained dogs, or bees - both of which can detect buried explosives? I know a guy in Chapel Hill NC who trained dogs in the 1990s to detect certain cancers, but claimed UNC Hospital dropped the idea because of payment difficulties. British researchers have trained dogs to detect cancers, such as prostate)
