Sniffing Out Explosives

A team of MIT researchers has discovered a new explosives detection method that is 30 times more sensitive than other methods. The team, led by chemistry professor Timothy M. Swager and Vladimir Bulovic, an assistant professor of electrical engineering and computer science, developed a semiconducting organic polymer that is extremely sensitive to vapors released by explosives such as trinitrotoluene (TNT). Exposure to ultraviolet light ordinarily causes this polymer to emit a beam of laser light. Molecules in the vapor from explosives, however, bind to the material’s surface, preventing lasing and extinguishing the beam.

The scientists believe that the technology could be as effective as trained bomb-sniffing dogs. “While dogs are pretty irreplaceable in terms of their ability to smell small amounts of explosives, they get tired very easily, and they can only work a couple hours a day,” says Aimee Rose, PhD ‘03, a visiting scientist at MIT and a researcher at Stillwater, OK-based technology development firm Nomadics. Rose also notes that the MIT technology, which grew out of her doctoral work, may be able to detect explosives at greater distances than dogs or currently available man-made sensors can–a particularly desirable feature for people hunting land mines and suicide bombs. Nomadics has licensed the technology, aiming to incorporate it into its existing line of bomb detectors within the next two years. – By Lisa Scanlon