Researchers at the Norwegian University of Science and Technology (NTNU) have developed an “artificial nose” that can detect volatile organic compounds (VOCs) with impressive accuracy. The breakthrough could revolutionize how we identify a host of hazards, including spoiled food, early disease, dangerous gases, air pollution, and more.
Professor Michael Cheffena of NTNU says the key to their innovative sniffer is actually an old technology that surrounds us daily: antennas. “We are literally surrounded by technology that communicates using antenna technology,” says Cheffena. “By giving the antennas sensor functions, the existing infrastructure can be used in new areas of application.”
Previous electronic noses have primarily utilized hundreds of sensors coated with different materials specially designed to detect certain chemicals. The artificial nose that Cheffena and his team have developed uses a single antenna with one type of coating, significantly reducing manufacturing costs, material usage, and power consumption.
The “nose” works by first transmitting radio signals at different frequencies into the surroundings. It then analyzes the signals that are reflected back. These signals change behavior based on the gases present, the patterns of which can be linked to specific VOCs.
While the naked eye can not detect VOCs, our human noses certainly can. For instance, bacterial activity in food produces volatile compounds that give off a specific odor, the first sign of spoilage. Research has shown that spoiled food causes about 250 health problems, including poisoning, allergies, and even cancer. Today, food spoilage is detected by very time-consuming bacteriological analysis.
Research fellow Yu Dang and lead author of a recently published paper about the new “nose” says their sensor distinguishes between the different gases it has been tested on with an accuracy of 96.7%. This result is not only on par with the performance of the best electronic noses to date, but in some areas, it even surpasses them.
All living organisms emit VOCs, as do many of the products we use and the materials that surround us. Given the large number of VOCs that are constantly circulating in most environments, distinguishing the innocuous chemicals from the harmful ones can be very challenging. Dang explained that it becomes even more difficult when isomers are also added to the mix.
Isomers are chemical compounds with the same molecular formula but slightly different atomic arrangements. These compounds have long been challenging for this type of sensor technology but Dang says their antenna sensor performs well even on these difficult compounds.
So far, the sensor technology has been tested on impact-damaged fruits and meats of varying ages. By adjusting the algorithms that detect the unique “fingerprints” of the different gases, the researchers believe the technology may also be able to smell diseases. While the results are promising, further research and development will be necessary to fully realize the potential of the technology. The research paper is available HERE. (Sources: Science Direct, NTNU Science Blog)
