Finding a needle in a haystack
MIT researchers have created a new detector so sensitive it can pick up a single molecule of an explosive such as TNT.To create the sensors, chemical engineers led by Michael Strano coated carbon nanotubes — hollow, one-atom-thick cylinders made of pure carbon — with protein fragments normally found in bee venom. This is the first time those proteins have been shown to react to explosives, specifically a class known as nitro-aromatic compounds that includes TNT.If developed into commercial devices, such sensors would be far more sensitive than existing explosives detectors — commonly used at airports, for example — which use spectrometry to analyze charged particles as they move through the air.“Ion mobility spectrometers are widely deployed because they are inexpensive and very reliable. However, this next generation of nanosensors can improve upon this by having the ultimate detection limit, [detecting] single molecules of explosives at room temperature and atmospheric pressure,”...