Silver is toxic to bacteria, and nanoparticles of the element offer promise as a coating for medical devices. But silver nanoparticles readily oxidize and clump together, losing their antibacterial activity. Chunhai Fan at the Chinese Academy of Sciences in Shanghai and his colleagues solved this problem by growing the particles on biocompatible silicon nanowires. This avoids the need for toxic or expensive chemicals to stabilize the silver nanoparticles.

The researchers show that exposure to a 10% solution of silver-coated nanowires froze population size in the bacteria Escherichia coli and Bacillus subtilis throughout a two-day test period.

Adv. Mater. doi:10.1002/adma.201001934 (2010)