Ions, not particles, make silver toxic to bacteria: Too small a dose may enhance microbes' immunity | Nanotechnology & Health | Scoop.it

"Researchers have settled a long-standing controversy over the mechanism by which silver nanoparticles, the most widely used nanomaterial in the world, kill bacteria. Their work comes with a Nietzsche-esque warning: Use enough. If you don't kill them, you make them stronger."