LOCUSTS
Researchers one step closer to bomb-sniffing cyborg locusts
News Release 14-Aug-2020
Study found locusts can quickly discriminate between different explosives' smells
If you want to enhance a locust to be used as a bomb-sniffing bug, there are a few technical challenges that need solving before sending it into the field.
Is there some way to direct the locust – to tell it where to go to do its sniffing? And because the locusts can't speak (yet), is there a way to read the brain of these cyborg bugs to know what they're smelling?
For that matter, can locusts even smell explosives?
Yes and yes to the first two questions. Previous research from Washington University in St. Louis has demonstrated both the ability to control the locusts and the ability to read their brains, so to speak, to discern what it is they are smelling. And now, thanks to new research from the McKelvey School of Engineering, the third question has been settled.
The answer, again: 'yes.'
In a pre-proof published online Aug. 6 in the journal Biosensors and Bioelectronics: X, researchers showed how they were able to hijack a locust's olfactory system to both detect and discriminate between different explosive scents – all within a few hundred milliseconds of exposure.
They were also able to optimize a previously developed biorobotic sensing system that could detect the locusts' firing neurons and convey that information in a way that told researchers about the smells the locusts were sensing.
"We didn't know if they'd be able to smell or pinpoint the explosives because they don't have any meaningful ecological significance," said Barani Raman, professor of biomedical engineering. "It was possible that they didn't care about any of the cues that were meaningful to us in this particular case."
Previous work in Raman's lab led to the discovery that the locust olfactory system could be decoded as an 'or-of-ands' logical operation. This allowed researchers to determine what a locust was smelling in different contexts.
With this knowledge, the researchers were able to look for similar patterns when they exposed locusts to vapors from TNT, DNT, RDX, PETN and ammonium nitrate – a chemically diverse set of explosives. "Most surprisingly," Raman said, "we could clearly see the neurons responded differently to TNT and DNT, as well as these other explosive chemical vapors."
With that crucial piece of data, Raman said, "We were ready to get to work. We were optimized."
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https://www.eurekalert.org/pub_releases/2020-08/wuis-ros081420.php