Explosives
Existing methods to detect explosives are bulky and need a trained operator. Reuters

An electronic chip with microscopic chemical sensors have been developed by Israeli scientists. It is said that this chip can detect explosives in air whose concentrations are as low as a few molecules for every thousand trillion.

The journal Nature Communications, on June 24, revealed that this nano-technology based-sensor is being developed by Tracense, a Tel Aviv company.

In the prototype phase, the detector can trace several types of explosives, even when several meters away from the source. It is portable and sensitive such that it can identify explosives that could be masked by strong chemicals.

The team wrote in the journal, "Different explosive species display a distinctive pattern of interaction with the nanosensing array, thus allowing for a simple and straightforward identification of the molecule under test." The Israeli team of scientists explained that the detection methods already existing can detect explosive types but only at higher concentrations and that they require bulky equipment and a trained operator who handles tedious sample preparations.

The materials used by the Tel Aviv company "offer the ability of incorporating multiple sensors capable of detecting numerous chemical threats simultaneously on a single miniature array platform." Changes in the electrical conductance of the sensors upon contact are caused by the clusters of transistors that are extremely sensitive to chemicals.

Explosives used in commercial blasting, military application and peroxide-based explosives like TNT, RCX, HMX, TATP and HMTD were detected by the device when it was being tested. TATP and HMTD, since they are used in home-made bombs, are difficult to detect by the methods already existing and this device could be a breakthrough.

At five meters and four meters frm the source, TATP and TNT particles could be identified. Through a paper filter, only five seconds of air sample collection had to be organised.

The Israeli team wrote, "These promising results demonstrate the potential capability of our sensing platform for the remote detection of explosive species."