Tuesday, April 24, 2018

It’s the bomb

URI chemical engineering professor creates prototype to detect bombs

new sensor detector
Alyssa Kelly, of Millville, Mass., and Otto Gregory,
URI chemical engineering professor and
new sensor detector. Photo: by Michael Salerno
It’s the size of a toolbox, and just as sturdy. It’s lightweight and even has a handle so it can be carried—quickly, if necessary—to different locations.

If all goes as planned, “The Digital Dog Nose” created by Otto Gregory, chemical engineering professor at the University of Rhode Island, could soon be placed at subway stations, train stations, airports and ports to detect bombs.

“We’ve made great progress on the project, and now we’re ready to get the word out,” says Gregory. “We’ve turned a corner with these latest developments.”

Two years ago, Otto and his students created a sensor to detect explosives commonly used by terrorists. 

One of the explosives is triacetone triperoxide, or TATP, which was used by terrorists during the Paris and Brussels attacks several years ago.

Terrorists use TATP because it is easy to make with chemicals that can be bought at pharmacies and hardware stores, attracting little attention from authorities. Only small amounts are needed to cause large explosions.


The goal of Gregory’s research is to find a way to detect the explosives’ vapors before the bomb detonates, launching quick evacuations and saving lives. The device is also significant because it works continuously, unlike bomb-sniffing dogs that can get tired.

The sensor Gregory created two years ago works by detecting the decomposition of nearby explosive molecules, triggering an alarm in the device. Back then, the sensor was in its early stages, mostly used for experiments in Gregory’s “Sensors and Surface Technology” laboratory on campus.

Over the last 15 months, Gregory and his students have been working intensely on the project and completed a prototype this summer. The team tested the prototype at the Naval Research Laboratory in Washington, D.C., in July, and at Rapiscan Systems, one of the top detection system manufacturers in the world, in August. The company is based in Andover, Mass.

“The testing exceeded our expectations,” says Andrew Rossi, of Portsmouth, who is pursuing his master’s degree in chemical engineering. “Both groups were impressed with our results. The prototype works—and works well.”

During the field trials, the prototype sucked in air contaminated with explosive molecules. Once the molecules hit the sensor, they broke apart and released heat, which, in turn, set off the sensor’s alarm.

The prototype was able to detect explosives at very low concentrations, as low as one molecule of an explosive in a billion molecules of air. “That’s amazing to us,” says Rossi. “The lower we can go, the less likelihood terrorists are going to get by security.”

Building the prototype was a challenge. “We were essentially taking something that was spread out on a big lab bench and condensing it into a small toolbox,” says Peter Ricci, of West Warwick, a junior studying chemical engineering. “We had to come up with the right box, tubing and piping.”

Alyssa Kelly, of Millville, Mass., says she appreciated the opportunity to work on a project that could save lives.

“I wasn’t expecting to learn so much in a research lab in such a short amount of time,” says Kelly, a junior majoring in chemical engineering. “I’ve learned a lot in the lab that I don’t necessarily learn in my classes, and it’s fulfilling to work on a project that could have a global impact.”

The next step is to make the prototype as small as a cell phone. The team is also reaching out to partners to market the product and to federal agencies involved with national security.

Gregory’s work is funded by the U.S. Department of Homeland Security. “I’m very excited about the future of the product,” he says. “We’re trying to make life safer for people throughout the world.”