Microbial resistance by so-called “superbugs” living in hospital environments causes 2-million U.S. infections and 23,000 deaths a year. Now hospital superbugs can be destroyed by covering bed rails, door knobs, and other surfaces with coating material inspired by a shark’s skin, according to new research led by UMass Amherst polymer scientist James Watkins and Chemical Engineering Professor Jessica Schiffman, along with a team of their graduate students. The research has been reported in a paper available online in the American Chemical Society journal ACS Applied Materials & Interfaces.
“The [sharks’] rippled skin stops bacteria sticking to them in the sea and causing infection, meaning they simply wash off,” said the article in Health Medicine Network. “Now scientists have designed a coating material infused with antimicrobials that is based on this patterned diamond-like texture of sharks’ skin. The scientists hope it will help combat growing resistance to antibiotics which the World Health Organization has described as a ‘global emergency.’”
As the article concluded, the topography of shark skin stops bacteria from sticking to sharks in the sea and causing infection, and instead bacteria simply wash off their bodies. Now the UMass scientists have designed coating material infused with antimicrobials and inspired by shark skin.
According to the UMass News Office, Watkins and Schiffman said they have designed an easily applied coating infused with photocatalytic antimicrobial titanium dioxide (TiO2) nanoparticles that decrease microbial attachment and deactivate those bacteria already attached to surfaces.
The researchers reported that in their experiments, shark-skin surfaces without nanoparticles reduced the attachment of E. coli by 70 percent compared to smooth films. But shark-skin surfaces with TiO2 nanoparticles exposed to ultraviolet light for one hour killed over 95 percent of E. coli and 80 percent of harmful Staphylococcus aureus.
As Watkins and Schiffman explained, when TiO2 nanoparticles are exposed to ultraviolet light, chemical reactions with water and hydroxide molecules form reactive hydroxyl radicals and superoxide ions that rupture the outer membranes of bacteria on contact and lead to cell death. Further, TiO2 nanoparticles are low-cost, widely available, and can be incorporated into transparent coatings, unlike more commonly known antimicrobials, such as silver and copper.
“These advantages make TiO2 an attractive candidate for use in high-touch antimicrobial surface coatings,” the scientists pointed out.
As Watkins and colleagues told Health Medicine Network: “Although commercial antibiotics are the most common way to kill bacteria, their misuse and overuse have led to widespread antibiotic resistance.” Watkins added that “New coatings for high-touch surfaces (such as bed rails, door knobs, etc.) that both limit the attachment of microorganisms and inactivate the persistent microbes are in high demand.”
This groundbreaking research was supported by the National Institutes of Health, National Science Foundation, and U.S. Army Laboratories. (June 2018)