Killing Resistant Bugs One Bandage At A Time: Gauze Developed With Microbicidal Coating

This microbicidal coating - which can be chemically bonded to gauzebandages, socks and even hospital bedding and gowns - kills the twomost common and harmful types of antibiotic-resistant bacteria thatcause infections in hospitals, the researchers said.

According to the National Institutes of Health, each yearnearly 2 million Americans contract infections while hospitalized.Antibiotic-resistant bacteria, such as methicillin-resistantstaphylococcus aureus and vancomycin-resistant enterococci, cause about70 percent of those infections.

"Those are the two classes of bacteria that are now epidemic inthe U.K.," said Gregory Schultz, Ph.D., director of UF's Institute forWound Research and one of the inventors who joined with aGainesville-based company to develop the coating. "It's a huge problemthere."

A patent is pending on the researchers' method of chemicallybonding the substance to fabrics and other materials. This methodallows the substance to be efficiently mass produced and permanentlyadhered to wound dressings or ready-to-wear clothing to make antifungaland microbicidal socks and underwear.

"What we developed in the lab has to be able to be adapted intoindustrial manufacturing, and the breakthrough came when we figured outhow to do that," Schultz said.

Clothing that kills athlete's foot and other fungi could helpU.S. soldiers in the field who often don't have time to change orshower, and the substance also could be added to hospital gowns andbedding to stop the spread of resistant bugs, said Schultz, who alsoserves as the company's vice president of clinical research anddevelopment.

Developed as the ultimate wound dressing, the coating blocksbacteria from reaching a wound and recolonizing there. UF researchersand scientists from the company presented their findings at the WoundHealing Society's annual meeting earlier this year, and the coating'sability to wipe out harmful bacteria and fungi was later confirmed inindependent laboratory tests.

The coating also was designed to keep bacteria from becomingresistant to it. Popular silver dressings work well as a bacterialbarrier but release ions that allow resistance to develop, Schultzsaid.

The structure of the microbicidal coating and the complexity ofthe process make it nearly impossible for bacteria to become resistantto it, Schultz said. The coating comprises thousands of nitrogenclusters that permanently bond to substances such as gauze and fabric.Other dressings use a process that allows molecules to diffuse into theair and into the wound, which can slow healing and increases the chancegerms will develop resistance.

"These technologies are especially timely given the threatsthat are facing the American public, such as antibiotic-resistant bugsoccurring in hospitals across the world," said Christopher Batich,Ph.D., a UF professor of biomedical engineering and one of thecoating's inventors. "This has the potential to be used widely."

The coating also does what it was created to do - aids healing,Schultz said. When added to gauze, it makes the materialsuperabsorbent, pulling excess moisture away from the sore. And itsmicrobicidal properties keep bacteria from growing in the wound andprotect it from infections. Bacteria in a wound "is like jet fuel forthese bugs," Schultz said.

"Gauze is still the most commonly used dressing for wounds," hesaid. "But the problem with gauze is when it absorbs fluid, it forms agreat avenue for bacteria and fungus to grow. This treatment actuallymakes the gauze absorb a little more fluid, (but) it'll keep the woundcleaner because it will keep the bacteria from getting back into thewound."

Clinical trials of the coating in gauze will be conducted at UF later this year.

Controlling moisture and staving off infection are two of themost important aspects of wound healing, said Jeffrey M. Davidson,Ph.D., president of the Wound Healing Society and a VanderbiltUniversity professor of pathology.

"Control of infection is very important for any type of wound,"he said. "Bacteria will produce substances that are harmful to thecells around them. They're trying to colonize. They're trying to make ahome for themselves."