US researchers have revealed a new sensor system which detects buried explosives. According to science news website (Science Daily), it is believed to be the first of its kind capable of detecting vapors from buried landmines and other explosive devices with the naked eye rather than advanced scientific instrumentation, engineers at the University of Connecticut (UConn) said. The key to the system is a fluorescent nanofiberous film that can detect ultra-trace levels of explosive vapors and buried explosives when applied to an area where explosives are suspected. A chemical reaction marking the location of the explosive device occurs when the film is exposed to handheld ultraviolet light, the researchers indicated. “Our initial results have been very promising,” Ying Wang of the UConn, who developed the system as a chemical engineering doctoral student, said. “We are now in the process of arranging a large-scale field test in Sweden,” he added. If there is no explosive vapor present, the recyclable film retains a bright fluorescent cyan blue color when exposed to ultraviolet light. If explosive molecules are present, the fluorescence is quenched and a dark circle identifying the threat forms on the film within minutes.