Nanowires keep surfaces sterile with silver and electricity

Metals like silver, gold and copper can kill bacteria and viruses. An electric current can also eliminate microorganisms. A team of U of A researchers combined the two approaches and created a new type of antimicrobial surface.

“It is a synergistic effect,” said physicist Yong Wang, one of the lead researchers on the project. “It’s not like 1+1=2. When we combine the two, it’s much more effective.”

In lab tests, the new technology, which uses thin nanowires of silver to carry a microampere electric current, eliminated all the E. coli bacteria on glass surfaces.

Along with Wang, the other inventors of the antimicrobial surface are physical chemist Jingyi Chen and physicists Hugh Churchill and Jin Hu.

Various noble metals, a group of metallic elements that resist corrosion, have antimicrobial properties, but silver has been shown to be the most effective at killing bacteria. The researchers created a network of silver nanowires, which both attacks bacteria and viruses and conducts electricity across the surface.

The microampere currently employed is low enough to be undetectable by human touch. And a solar cell no bigger than a fingernail could power the antimicrobial surface.

The technology not only kills bacteria and viruses but also keeps them from growing, creating a sterile surface.

U of A’s Technology Ventures is pursuing patent protection for this invention and is seeking companies that are interested in commercializing the technology.

Wang can imagine many applications for the invention. Door handles or countertops could be made germ resistant. Medical facilities, food facilities or restaurant kitchens could incorporate the antimicrobial technology.

The network of tiny, electrified silver wires could even be applied to cloth, creating highly effective filters for ventilation systems or even personal protective equipment, like masks and gowns, to provide an extra barrier against pathogens.