Nano-sized carbon tubes coated with DNA can create tiny sensors with abilities to detect odors and tastes, according to researchers at the University of Pennsylvania and Monell Chemical Senses Center.
Arrays of these nanosensors could detect molecules on the order of one part per million, akin to finding a single person in Times Square on New Years’ Eve. The nanosensors were tested on five chemical odorants, including methanol and DNT, a chemical frequently used in explosives. They could sniff molecules out of the air or taste them in a liquid, suggesting applications ranging from domestic security to medical detectors.
“What we have here is a hybrid of two molecules that are extremely sensitive to outside signals: single stranded DNA, which serves as the ‘detector,’ and a carbon nanotube, which functions as ‘transmitter,'” said A. T. Charlie Johnson,from Penn. “Put the two together and they become an extremely versatile type of sensor, capable of finding tiny amounts of a specific molecule.”
According to the researcher, an array of 100 sensors with different response characteristics and an appropriate pattern recognition program would identify a weak known odor in a strong and variable background. “There are few limits as to what we could build these sensors to detect, whether it is a molecule wafting off an explosive device or the protein byproduct of a cancerous growth,” Johnson said.