Researchers at Temple University's School of Medicine have developed a new biosensor that "sniffs out" explosives and could one day be used to detect landmines and deadly agents such as sarin gas. The sensor is made of a genetically engineered yeast strain with mammalian (rat) olfactory-signaling machinery that was genetically linked to the expression of green fluorescent protein.
They cloned into the yeast cells individual rat olfactory receptors. When the receptor "smells" the odor of DNT, an ingredient in the explosive TNT, the biosensor turns fluorescent green. The team is now perfecting the utility of the biosensor to improve its response time. The potential therapeutic applications extend beyond the detection of chemical agents, and include screening of experimental medicines.
The biosensor soon will be incorporated into a handheld or remote device that can be left at a location and monitored from a distance. The research was sponsored by the U.S. Defense Advanced Research Projects Agency (DARPA).