Silverware became popular centuries ago partly because it was a precious metal and thus a status symbol, but also because the health qualities of silver have been known since Roman times. Back then wealthy folks even gave their kids a silver spoon to suck on to ward-off the plague (hence the saying). Modern science understands how silver has anti-bacterial qualities, but the trick in delivering silver accurately into a wound nowadays is getting the dosage right since silver is toxic in high concentrations. That’s what research at the University of Wisconsin-Madison is tackling, with a novel delivery approach for silver nanoparticles.
The research team has perfected a way of delivering silver nanoparticles onto skin in a layer just a few molecules thick – thereby forming an excellent barrier but not over-dosing the region and killing skin cells – by borrowing a technique that’s long been used to apply ink in molecule-thick layers: rubber stamping. The polyelectrolyte multilayer coating, mixed with micrometre-sized beads of silver nanoparticles (which the team found was the most efficient way to ensure delivery) was “assembled” on a rubber stamp and was then placed on wounds from cadaver skin to test its efficiency.
Small doses of bacteria (common skin bacteria staphylococcus epidermidis and pseudomonas aeruginosa – both of which can run rampant and cause infections) were applied to the area. After roughly 12 hours 99.999 per cent of the bacteria were killed and the bacteria-defeating effect was still reliable up to around 48 hours.
To check that the treatment didn’t actually interfere with normal wound-healing, the scientists tried it on diabetic mice and are currently investigating wound healing on mice and pigs (particularly interesting as pig skin is analogous to human skin in many ways).
So in the future, a trip to ER to stitch a wound could result in patients wearing a rubber stamp healing treatment, too.
Image via Flickr user soopahgrover.