Scanning electron microscopy image of nanocomposite film. Image Credit: Rensselaer/Ravindra C.Pangule and Shyam Sundhar Bale

Building on an enzyme found in nature, researchers at Rensselaer Polytechnic Institute have created a nanoscale coating for surgical equipment, hospital walls, and other surfaces that safely eradicates methicillin resistant Staphylococcus aureus (MRSA), the bacteria responsible for antibiotic resistant infections.

“We’re building on nature,” said Jonathan S. Dordick, the Howard P. Isermann Professor of Chemical and Biological Engineering, and director of Rensselaer’s Center for Biotechnology and Interdisciplinary Studies. “Here we have a system where the surface contains an enzyme that is safe to handle, doesn’t appear to lead to resistance, doesn’t leach into the environment, and doesn’t clog up with cell debris. The MRSA bacteria come in contact with the surface, and they’re killed.”

In tests, 100 percent of MRSA in solution were killed within 20 minutes of contact with a surface painted with latex paint laced with the coating.

Safe to Use

The new coating marries carbon nanotubes with lysostaphin, a naturally occurring enzyme used by non-pathogenic strains of Staph bacteria to defend against Staphylococcus aureus, including MRSA. The resulting nanotube-enzyme “conjugate” can be mixed with any number of surface finishes — in tests, it was mixed with ordinary latex house paint.

Unlike other antimicrobial coatings, it is toxic only to MRSA, does not rely on antibiotics, and does not leach chemicals into the environment or become clogged over time. It can be washed repeatedly without losing effectiveness and has a dry storage shelf life of up to six months.

The research, led by Dordick and Ravi Kane, a professor in the Department of Chemical and Biological Engineering at Rensselaer, along with collaboration from Dennis W. Metzger at Albany Medical College, and Ravi Pangule, a chemical engineering graduate student on the project, has been published in the July edition of the journal ACS Nano, published by the American Chemical Society.