Washington, May 28 : Sniffer dogs have been touted as the best portable explosive-detectors, till date. But now researchers at the University of Florida in Gainesville, US, have developed a new portable technique based on the way explosives absorb and reflect light. Before detecting an explosive, a number of techniques require significant preparation of a sample, such as dissolving explosive residue in a solution, or collecting large volumes of air containing explosive vapour.
However, this new method requires little or no sample preparation, used in most of the other detecting methods- which ensure a quick and reliable detection but are not truly portable.
In this technique, developed by Rolf Hummel and colleagues at the University of Florida in Gainesville, US, the device shines ultraviolet, infrared and visible light onto two sample areas at the same time then calculates the difference in reflectance between them for each part of the spectrum.
In case, explosives are present at one sample area, but not the other, the characteristic signature of reflected light should show up clearly in this difference measurement.
This enables easy identification of the explosive by comparing the signature with a database stored in the detector.
According to Hummel, his device is quick, simple to operate and requires none of the care and attention needed by of the current best portable explosives detectors - sniffer dogs.