Engineering a Bloodhound

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Seen here, a model of molecular dynamics depicting a single strand of DNA is seen wrapping around a carbon nanotube.

A bloodhound can sniff out the smallest chemical traces. What if researchers could create an “artificial nose” with the same acuity as a canine? It just might be a revolution in chemical sensing.

Using a technique involving DNA and carbon nanotubes, researcher Jeff Stuart at Lockheed Martin Advanced Technology Laboratories is taking the initial steps toward mimicking the bloodhound’s remarkable nose. Stuart is working to advance academic technology developed by Dr. Charlie Johnson, professor in the department of Physics and Astronomy at the University of Pennsylvania.

“Dr. Johnson has done some incredibly innovative work that has a lot of potential – we want to bridge the gap between the laboratory and commercial environment and bring the technology to a point where it can be manufactured,” says Stuart.

Stuart envisions a variety of uses for his artificial nose. "Having a multiple-use chemical sensor would transform how we conduct sensing today. Instead of testing for one or two analytes, the sensor could be adapted to detect virtually any chemical target.

“Beyond the typical scenarios of contraband detection and search and rescue operations, a sensor like this could be used for individual biometric identification, detection of toxic chemicals, quality control, environmental monitoring, and more,” Stuart explains.

So how does this technology work? Researchers at the University of Pennsylvania and the Monell Chemical Senses Center (Philadelphia, Pa.) found that DNA wrapped around a carbon nanotube converts the DNA’s unique response to chemicals into an electrical signal.

In effect, the nanotube “feels” the changes experienced by the DNA as it interacts with other molecules, explains Jeff Stuart, the principal researcher for the Lockheed Martin project. Those changes depend on the DNA sequence, each of which will have a different response to chemical analytes, he notes.

“My first goal is to use computational physics to understand how this sensor works," says Stuart. "The better we understand it, the better we can engineer a device."

Pattern recognition techniques will be used to detect and identify chemicals. Explains Stuart, “Let’s say you have a matrix of a thousand sensors. You would use that matrix to generate digital patterns of chemicals and odors. Each odor or chemical will produce a different pattern, which is then stored and associated with the smell – in this way the sensor is trained to recognize odors much like mammals do. When the sensor encounters that odor again, it can pinpoint it exactly by comparison to previously stored patterns.”

“Lockheed Martin has vast experience working with carbon nanotubes in sensors, electronics, and structures, especially in a manufacturing environment," Stuart says. "If you put all these together, you have a really compelling case for how we can use the research to engineer a device for some of these applications.

"With our expertise, I think we could make this technology ready for the market in about five years,” says Stuart.

Posted February 8, 2013

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Researcher Jeff Stuart of Lockheed Martin Advanced Technology Laboratories.


highlights
  • Using a technique involving DNA and carbon nanotubes Lockheed Martin Advanced Technology Laboratories is taking the initial steps toward mimicking the bloodhound’s remarkable nose.
  • In effect, the nanotube “feels” the changes experienced by the DNA as it interacts with other molecules.
  • Pattern recognition techniques will be used to detect and identify chemicals.