Scientists develop sensor to detect chemicals used in high-energy explosive
Indian scientists have for the first time developed a thermally
stable and cost-effective electronic polymer-based sensor for rapidly detecting
nitro-aromatic chemicals used
in high-energy explosives, the Department of Science and Technology (DST) said
on Friday.
The detection of explosives without
destroying them is essential for protection, and criminal investigations,
minefield remediation, military applications, ammunition remediation sites,
security applications, and chemical sensors play a vital role in such cases, it
said.
Explosive poly-nitroaromatic compounds can be analysed usually by
sophisticated instrumental techniques. But the requirements for quick decision
making in criminology laboratories or reclaimed military sites or to detect explosives in
possession of extremists often require simple, cheap, and selective field
techniques, which will be non-destructive in nature, the DST said.
Non-destructive sensing of nitroaromatic chemicals (NACs) is
difficult, it said.
While earlier studies are based mostly on photo-luminescent
property, detection on the basis of conducting property has not been explored
so far, it said.
Detection on the basis of conducting property helps in making a
handy detection device where results can be seen with the help of LED, the
department said.
To overcome such disadvantages, a team of scientists, led by
Neelotpal Sen Sarma from the Institute of Advanced Study in Science and
Technology, Guwahati, an autonomous institute of the DST, has developed a
layer-by-layer (LBL) polymer detector consisting of two organic polymers --
poly-2-vinyl pyridine with acrylonitrile (P2VP-Co-AN) and copolysulfone of
cholesteryl methacrylate with hexane (PCHMASH), it said.
This undergoes a drastic change in impedance (resistance in an ac
circuit) in the presence of very low concentration of NACs vapour within a few
seconds, the DST said.
Here, picric acid (PA) was chosen as the model NAC, and a simple
and cost-effective electronic prototype was developed for visual detection of
PA. The team has filed a patent for the novel technology funded by the
Department of Electronics and Information Technology, it said.
"An electronic sensing device build around a polymer gas
sensor can quickly detect the explosive on-site," said Sarma.
Comments
Post a Comment