The terror threat around the world is at one of its highest. For those interest in security and bomb detection the task becomes ever more complicated as terrorists find new ways to conceal explosive devices. In order to help security forces to keep the world safer, scientists are using quantum technology.
The new method for explosives detection is based on sensor technology, which uses nano-particle array systems. This is a relatively new field and has advanced considerably in recent years. The first wave of sensors was directed towards the medical field and focused on disease detection. Now, the technology is being reviewed for homeland security.
The explosive-detecting sensors are based on fluorescent, semiconducting nanoparticles termed "quantum dots." The first wave can detect most chemicals capable of causing explosions, but they are limited in differentiating between the various types of explosive compounds that make-up an would-be terrorist's armory. Knowing the type of explosive is important in terms of the strategy used to defuse it.
To come up with something altogether more effective, researchers have combined
three different-colored quantum dots and tested the mixture against five very different explosive compounds. The explosives included TNT and pentaerythritol tetranitrate (PETN) (the latter being the explosive “shoe bomber” Richard Reid
attempted to use.)
Laboratory studies, conducted at University College in London, have shown that within 10 seconds the explosives bound to the quantum dots in different ways. The variation in binding changes the fluorescence and created identifiable fingerprints for each type. The scientists conclude their approach can be applied to explosives monitoring, although further development is required.
The research is published in
the journal ACS Nano
. The paper is titled: "Multichannel Detection and Differentiation of Explosives with a Quantum Dot Array."