Light Activated Material Kills Super Bugs on Hospital Surfaces

Light Activated Material Kills Super Bugs on Hospital Surfaces

I’m sure you’ve heard people say to never go to a hospital if you’re sick because the hospital stay will kill you first. Sadly, there’s truth to the saying. Healthcare associated infections (HAI) are common with about one person of of every 25 having an HAI on any given day in the US, according to the Center for Disease Control (CDC).

To add insult to injury, the longer the stay, the more likely it is that your life is in danger than when you check in. In 2011, 75,000 patients with HAIs died while hospitalized.

The emergence of infectious super bugs such as HA-MRSA adds an element of urgency to fighting the spread of bacteria. These organisms are hard, sometimes impossible, to treat.

Help is on the way in the form of a light-activated material for hospital walls and surfaces that contains bacteria-killing molecules that has a great chance of keeping those superbugs from taking over.

Ethel Koranteng, a chemist at University College London,  and colleagues developed a material to make hospital surfaces self-disinfecting and described it at a Materials Research Society confereren.

Naturally antimicrobial metals such as copper and steel are difficult to sculpt around uneven surfaces. But the new polymer-based material could be fashioned into a flexible film that covers computer keyboards, or molded into rigid, plastic like casings that enclose phone handles, bed rails and other surfaces especially prone to contamination.

Unlike other polymer-based antimicrobial coatings that rely on a spritz of water to release bug-killing particles, the new material is activated by overhead lighting.

The covering is made of polyurethane embedded with tiny semiconductor nanoparticles called quantum dots and particles of a purple dye called crystal violet. When the quantum dots absorb ambient light, they transfer some of that energy to nearby dye particles, causing the crystal violet to release a kind of high-energy oxygen molecule that kills microbes.

In lab tests, the material killed 99.97 percent of MRSA, the strain of Staphylococcus aureus that is resistant to methicillin and other antibiotics, and 99.85 percent of a multidrug-resistant strain of E. coli. For both experiments, the researchers used much higher concentrations of microbes than those typically found on hospital surfaces, Koranteng said.

These results are heartening. The new material could become an important element in fighting infections in any healthcare setting, such as the one in four nursing homes through which infections often run rampant. Along with the ongoing prioritization of hygienic practices, QD-CV coatings may mean that someday staying in a hospital will no longer be taking on an additional risk on top of whatever it was that made you check in in the first place.