MIT researchers have developed a new type of tiny, smartphone-readable particle that could tell if a food product is counterfeit.The particles, which are invisible to the naked eye, contain coloured stripes of nanocrystals that glow when lit up with near-infrared light.
Easily manufactured and integrated into a variety of materials, the particles can withstand extreme temperatures, sun exposure and heavy wear, according to Professor Patrick Doyle, a chemical engineer who is the senior author of a paper describing the particles in the journal Nature Materials.