According to folklore, silver bullets kill werewolves, but in the real world, researchers want to harness this metal to fight another deadly foe: bacteria. Recently, scientists have tried to develop a silver coating for implantable medical devices to protect against infection, but they’ve had limited success. In a study in ACS Central Science, one team describes a new, long-acting silver-ion releasing coating that, in rats, prevents bacteria from adhering to implants and then kills them.
Sometimes medical care requires surgeons to implant a device, such as a tube to drain a wound or the bladder, or to deliver medication directly into the blood. However, bacteria can attach to and collect on the surfaces of these devices, creating a risk for dangerous infections. Researchers have been working to develop bacteria-repelling coatings, including those containing silver, which is known to kill microbes. However, their efforts have faced numerous challenges: Silver can also be toxic to human cells, and it’s difficult to make a coating that continually releases small amounts of the metal over long periods, for example. Dirk Lange and Jayachandran Kizhakkedathu wanted to identify a formula that could overcome these and other difficulties.