The Galilee Medical Center is testing Maya – a 3D-printed sticker that Technion Professor Eyal Zussman has developed. When stuck on a surgical mask, it adds the extra layer of a biological filter. Its nanometric fibers are coated with disinfectants to effectively neutralize viruses.
https://www.calcalistech.com/ctech/articles/0,7340,L-3804900,00.html