TAU chemists develop explosives-detecting sensors

Nanotechnology-based electronic sensor is fast, highly portable and more sensitive and reliable for detecting explosives than sniffer dogs are.

Within days of revelations that al-Qaida mailed an explosives-packed printer from Yemen destined for Chicago synagogues, Tel Aviv University said on Tuesday that its researchers have developed a powerful electronic sensor able to detect many kinds of such dangerous chemicals.

The nanotechnology-based sensor is fast, highly portable and more sensitive and reliable for detecting explosives than sniffer dogs are, according to Prof. Fernando Patolsky of the Sackler School of Chemistry, who headed the research team.

The development is attracting attention among scientists and security companies around the world, especially after an article appeared in the prestigious journal Angewandte Chemie. The Israeli company Nanergy, Inc., which develops fuel cells for portable electronics and stationary backup power, has developed a prototype based on the patent, and is already in contact with companies that develop explosives sensors.

Patolsky said that existing methods of detecting explosives such as TNT have drawbacks – their high cost, bulk, long decoding times and the need for expert or laboratory analysis.

“There is a need for a small, inexpensive, handheld instrument capable of detecting explosives quickly, reliably and efficiently,” he said on Tuesday.

The sensor uses arrays of silicon nanowires to form an electronic nanotransistor that is supersensitive to the surrounding electrical environment.

The research team coated the wires with a compound that binds to explosives. To enhance the chips’ sensitivity, the scientists equipped them with 200 individual sensors for detecting a large variety of explosives with an unprecedented degree of reliability, said Patolsky, who returned to Israel from Harvard University just four years ago.

Two major advantages of the new sensor are that it can be transported from place to place by hand and can detect explosives from afar. For example, it can be mounted on a wall, with no need to bring it into contact with the item being checked. Unlike other sensors, it enables definitive identification of the explosive that it has detected, with no detection errors or failures, Patolsky maintained.

The research team is known as one of the world’s leading teams involved in the development of nanometric sensors for the detection of chemical and biological molecules. Such sensors may be used to detect not only explosives, but also biological toxins such as anthrax, cholera and botulinum.

The technology’s applications may be useful not only in the national security sphere, but in the biological and medical spheres as well.