A research team from RMIT University in Melbourne, Australia, has devised an ultra-thin 2D antimicrobial coating that could be used to counter drug-resistant bacteria and fungal cells. The coating can be applied to wound dressings and implants to prevent infections from pathogens.
The coating is made from a 2D material that has only previously been intended for next-generation electronics. However, according to the study published in the American Chemical Society's journal Applied Materials & Interfaces, the material can be repurposed with black phosphorus to heighten antibacterial and antifungal properties.
"These pathogens are responsible for massive health burdens and as drug resistance continues to grow, our ability to treat these infections becomes increasingly difficult. We need smart new weapons for the war on superbugs, which don't contribute to the problem of antimicrobial resistance," says co-lead researcher Dr. Aaron Elbourne, who is a Postdoctoral Fellow in the School of Science at RMIT. Fungal infections are responsible for roughly 1.5 million deaths globally every year while antibiotic resistance kills approximately 700,000 people annually. These numbers are expected to rise over the next decades unless there are major advances in antibacterial therapies.
The coating works by way of cellular oxidation of bacterial and fungal cells, leaving human cells alone. “Our nano-thin coating is a dual bug killer that works by tearing bacteria and fungal cells apart, something microbes will struggle to adapt to. It would take millions of years to naturally evolve new defenses to such a lethal physical attack. While we need further research to be able to apply this technology in clinical settings, it's an exciting new direction in the search for more effective ways to tackle this serious health challenge," notes Elbourne.
"Black phosphorus breaks down in the presence of oxygen, which is normally a huge problem for electronics and something we had to overcome with painstaking precision engineering to develop our technologies," adds co-lead researcher Associate Professor Sumeet Walia of RMIT's School of Engineering. "But it turns out [that] materials that degrade easily with oxygen can be ideal for killing microbes -- it's exactly what the scientists working on antimicrobial technologies were looking for. So our problem was their solution."
The team demonstrated the coating’s effectiveness at destroying 99% of cells of five common bacteria strains (including E. coli and drug-resistant MRSA) and five types of fungus (including Candida auris) within two hours. Additionally, the black phosphorus coating also self-degraded within 24 hours of application, meaning that it would be safe for use in the human body.