Researchers have successfully incorporated “photosensitizers” into a range of polymers, giving those materials the ability to render bacteria and viruses inactive using only ambient oxygen and visible-wavelength light. The new approach opens the door to a range of new products aimed at reducing the transmission of drug-resistant pathogens.
“Our goal with this work was to develop materials that are self-sterilizing, nontoxic and resilient enough for practical use,” says Reza Ghiladi, associate professor of chemistry at NC State and co-corresponding author of a paper on the work. “And we’ve been successful.”
The new approach involves incorporating photosensitizers into hydrophobic, semi-crystalline elastomers, which are waterproof and mechanically resilient – while also allowing oxygen to access the photosensitizers. What’s more, the distribution of photosensitizers in the material means that it will retain its antimicrobial properties even if the surface of the material is scratched or worn away.
“This paper focuses on one class of polymers, but it is a fundamental proof of concept that demonstrates the ability to put these photosensitizers into a range of robust ‘soft’ materials without sacrificing functionality,” says Richard Spontak, distinguished professor of chemical and biomolecular engineering, professor of materials science and engineering at NC State and co-corresponding author of the paper.. “This is the tip of the iceberg.”
In lab testing, the researchers found that a photosensitizer-embedded polymer inactivated at least 99.89 percent of five bacterial strains — and 99.95 percent of two viruses — when exposed to light for 60 minutes.
“We’re currently looking for partners to work with us on research using these materials to address pathogens of national importance, such as Clostridium difficile, which is classified as an ‘urgent’ hazard level by the CDC, and anthrax.”
“And while we want to pursue applications in high-tech environments, such as hospitals, we think there is a huge potential for improving health in impoverished areas,” Spontak says. “If we can develop self-sterilizing items that help limit the spread of disease in areas with limited medical resources, we could save a lot of lives.”