High-tech wound dressing is shown to fight infection

University of Wisconsin researchers have demonstrated how an ultra-thin layer of polymer impregnated with a surgical antibacterial can help healing by preventing infection.

Using a technology developed in the lab of Nicholas Abbott, a professor of chemical engineering, Abbott, Ankit Agarwal and colleagues crafted a polymer nanofilm containing chlorhexidine, and then stamped it onto a biologic wound dressing that is currently on the market.

The commercial dressing is sometimes called a skin substitute because it is embedded with biological compounds that promote healing, and so it is a prime treatment for burns and persistent wounds. But Agarwal, an honorary associate in the UW-Madison Department of Chemical Engineering, notes that infection can block healing in as many as 20% of patients.

To fight infection, physicians can place a gauze containing chlorhexidine on the biological dressing. But the high concentration of the anti-bacterial kills skin cells, slowing healing, and the gauze must be re-applied.

The nanotechnology approach releases a much smaller dose of chlorhexidine. This approach blocked infection while promoting healing.

In the first study to test specially treated nanofilms, the material reduced the number of bacteria colonies by 99.9% after three days, Agarwal said.

The goal was to reduce the antibacterial agent so that “it’s not toxic to the healing cells, just to bacteria,” he said.
Full findings appear in the journal Biomaterials.