Although experts predict that a practical device is at least five years away from actual use at airports, on battlefields and elsewhere, the researchers say their new sensor will improve the sensitivity and reliability of current prototypes. Their findings are reported in the November 1 issue of Analytical Chemistry, a peer-reviewed journal of the American Chemical Society, the worlds largest scientific society.
Trained dogs and people armed with dirt-clearing probes or metal detectors are the current methods of choice for landmine detection. But dogs get fatigued easily, while human minesweepers are at risk of serious injury and death. The new sensor could ultimately help save lives and reduce injuries, says David R. Walt, Ph.D., a professor of chemistry at Tufts University in Medford, Mass., and lead investigator in the study.
But first, he says, the sensors must be made more user-friendly. And they must be able to solve a wider array of odor recognition problems, says Walt, who holds several patents on the new sensor technology.
His and other sensors in development tend to degrade over time, Walt says, just as the human nose looses its ability to sense and remember certain odors as people age. So the sensors need to be retrained or resensitized frequently to recognize target odors, he says.
In a process akin to replacing a dead battery with a fresh one, the new sensor is made with specially designed disposable fluorescent polymer beads. Because the beads are conditioned not to need odor-recognition training, degradation and retraining problems could be eliminated, Walt and his associates say.
Billions of the sensor beads can be made at once, as needed, whether daily, weekly or yearly, providing a continuous replacement st
Contact: Beverly Hassell
American Chemical Society