Saturday, January 8, 2011
Out-sniffing the dogs
A research team in Israel has developed an electronic sensor said to be even more sensitive and reliable than the nose of a sniffer dog.
It doesn't have a nose of its own, but the small, portable sensor developed by a research team at Tel Aviv University (TAU) has not had a single detection error, as it correctly identified multiple types of explosives in every lab test administered to date.
Based on recent advances in nanotechnology, the device is made from an array of silicon nanowires coated with a compound that binds to explosives to form an electronic nanotransistor.
Security companies and fellow scientists are already paying special attention to the invention developed by lead researcher Prof. Fernando Patolsky and his team from TAU's Raymond and Beverly Sackler School of Chemistry.
In addition to its perfect detection record for explosives - including those used in the recent Yemeni bomb threat - in the future the sensor may also be used to detect toxins and other biological threats, such as anthrax, cholera or botulinum, the team reports. And looking beyond national security, the sensor offers attractive applications in the medical field.
Definitive explosive ID
Patolsky notes that the sensor is especially effective at detecting TNT. Existing methods and devices used to trace the explosive have the drawbacks of high cost, lengthy decoding times, size, and a need for expert analyses: "There is a need for a small, inexpensive, handheld instrument capable of detecting explosives quickly, reliably and efficiently," he says.
The researchers are adamant that the new sensor can out-sniff even a champion sniffer canine.
To enhance the sensitivity of chips in the nanotransmitter, the scientists developed each one with 200 individual sensors that work in harmony to detect different kinds of explosives with an unprecedented degree of reliability, efficiency and speed.
One major advantage of the new sensor is its portability; it can be carried from place to place by hand. It is also capable of detecting explosives at a distance, as it can be mounted on a wall, with no need to bring it into contact with the item being checked. And unlike other explosives sensors, it enables definitive identification of the explosive that it has detected.
World-leading research team
Scientific findings on the sensor were published recently in the prestigious Angewandte Chemie journal and the American company Nanergy has developed a prototype based on the patent.
It is already in contact with potential partners to develop explosives sensors for the commercial market.
With Patolsky, who recently returned to Israel from Harvard University at its helm, the research team is considered to be one of the world's leaders in developing nano-based sensors that can detect chemical and biological molecules.
It seems that dogs, previously heralded as man's best bomb detector, will be sent back to the doghouse.