Colorful, Magnetic Janus Balls Could Help Foil Counterfeiters

Anti-counterfeiting tags to help identify knockoffs of popular handbags, shoes, and other items are in high demand. Now, researchers reporting in ACS Nano have developed tiny, two-sided “Janus balls” that show their colored side under a magnetic field. Produced by the American Chemical Society (ACS), this video, which is part of ACS’ Headline Science, shows how these microparticles could help foil counterfeiters. Courtesy of ACS Nano.