They embedded the plants' leaves with carbon nanotubes—tiny cylinders of carbon that can detect “nitroaromatics"—chemical compounds often used in landmines and other explosives. When one of these chemicals compounds is absorbed naturally by the plant (either in the air or through groundwater), the embedded nanotubes emit a fluorescent signal that can be read with an infrared camera, MIT said. "The camera can be attached to a small computer similar to a smartphone, which then sends an email to the user," the school said in a release.
The study, led by Min Hao Wong, an MIT graduate student, and Juan Pablo Giraldo, a former MIT postdoc now working as an assistant professor at the University of California at Riverside, was outlined in a paper in the Oct. 31 issue of Nature Materials.
These results " open t he do or to the use of wild-typ e plan ts fo r infrared comm unication in wide ar eas, and real-time moni to ring of en viro nmen ts such as cities, crop f ields, high-s ecur ity facilities, and homes ," the paper concluded. Watch a video about how it works here: