Darpa’s Butterfly: Inspired sensors light up at chemical threats

Darpa’s Butterfly: Inspired sensors light up at chemical threats

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Exploded zoom of nano photonic sensors "scales" on a butterfly wing measuring 50 by 100 microns each

It’s not the first time bugs are being heroes.  In 2005, the Defense Advanced Research Projects Agency supported scientists in using honeybees in bomb detecting devices.  Last year, DARPA-backed researchers at Agiltron Corporation began implanting larvae with micromechanical chemical sensors.  Now, the agency has awarded $6.3 million to a group led by GE Global Research for developing chemical weapon sensors inspired by butterflies.

Dr. Radislav Potyrailo, chemist and lead scientist at GE Global Research, describes the nanostructures on the scales of butterfly wings as “tiles on a roof.”  In a chemical response based on photonics, these “tiles” change spectral reflectivity depending on their exposure to different vapors.  As Potyrailo wrote in a 2007 article in Nature Photonics, “this optical response dramatically outperforms that of existing nano-engineered photonic sensors.”

Based on this discovery, Potyrailo and his team are developing single sensors that are tailored to detect certain types of chemical agents or explosives.  These sensors light up when they encounter threats and are designed to function regardless of any cross-contamination from non-threatening airborne artifacts or environmental elements.  “This is a fundamentally different approach,” Potyrailo told Wired. “Existing sensors can measure individual gases in the environment, but they suffer, big time, from interferences. This approach overcomes that hurdle.”

According to Potyrailo, “It would be science fiction to say ‘here is my sensor, it can selectively detect 1,000 different chemicals.  But what we’re saying is that we can detect and distinguish between several important chemicals – without making mistakes, without false responses.”

Measuring about 1 x 1 cm a piece, the sensors could be embedded in clothing, installed in buildings or deployed “like confetti” over extensive regions.  This new technology can even be used for water purification tests and food safety, giving butterflies in your stomach a whole new meaning.