Zapping nanoparticles into nail polish

Marcus Lau found inspiration lodged somewhere in the 50-odd bottles of nail polish in his fiancé’s bathroom drawers. “I soon realized that one thing was always missing: a real gold-containing polish,” he says, now happily married. It occurred to Lau that he could use the laser in the lab at the University of Duisburg-Essen, where he is a postdoc, to create a cosmetic out of gold nanoparticles. Working with his mentor Stephan Barcikowski and graduate student Friedrich Waag, Lau developed a method to directly integrate metal nanoparticles into nail polish (Ind. Eng. Chem. Res. 2017, DOI: 10.1021/acs.iecr.7b00039). The researchers placed a metal plate—gold, silver, platinum, or a gold-silver alloy—into a glass vessel and covered it with clear, colorless nail polish. They then used laser ablation to zap metal nanoparticles into the polish over the course of 15 minutes. The nanoparticles have no corona of residual chemicals or capping agents, Barcikowski points out, which are tricks typically used to get nanoparticles into viscous liquids. In addition to creating metallic nail polishes, the chemists note that the coatings could be used for biomedical applications. The nanoparticles in the silver polish, specifically, appear to break down into silver ions, which have antibacterial properties.