Researchers have developed a black phosphorus-based nanotechnology that kills more than 99% of drug-resistant bacteria. This innovative material degrades upon contact with oxygen, producing reactive oxygen species that kill bacteria and can be used in wound dressings, implants and medical devices to treat and prevent bacterial infections.

Co-lead researcher Professor Sumeet Walia from RMIT University said the study showed how their innovation provided a rapid antibacterial effect and then disintegrated itself once the threat of infection was removed.

"The beauty of our innovation is that it's not a simple coating - it can actually be integrated into the common materials, plastics and gels of the device, making it antimicrobial," said Walia, from RMIT's School of Engineering.

A study led by RMIT University shows that black phosphorus can effectively kill microorganisms when applied as a nanoscale layer on surfaces used to make wound dressings and implants such as cotton and titanium, or when incorporated into plastics used in medical devices.

Black phosphorus is the most stable form of phosphorus - a mineral found naturally in many foods - in an ultra-thin form that degrades easily in the presence of oxygen, making it ideal for killing microorganisms.

"When a nanomaterial breaks down, its surface reacts with the atmosphere, producing so-called reactive oxygen species," Walia said. "These species ultimately help tear apart bacterial cells, and our antibacterial nanotechnology quickly eliminated more than 99 percent of bacterial cells, significantly exceeding current common therapies for treating infections."

New research tested the effectiveness of nanoscale black phosphorus flakes against five common strains of bacteria, including E. coli and drug-resistant Staphylococcus aureus.

The global war against superbugs

Co-lead researcher Dr Aaron Elbourne from RMIT University said healthcare workers around the world urgently need new treatments to overcome antibiotic resistance.

"Superbugs - pathogens that are resistant to antibiotics - pose a huge health burden, and as resistance increases, our ability to treat these infections becomes increasingly challenging," said Elben, a senior research fellow at RMIT University's School of Science. "If we can make our invention a commercial reality in the clinic, these superbugs around the world will have no idea what's hit them."

Lead researcher Dr Zlatko Kopecki from the University of South Australia and his team conducted preclinical trials showing that daily topical use of black phosphorus nanosheets can significantly reduce infections.

"This treatment was as effective as the antibiotic ciprofloxacin in eradicating wound infection and accelerated wound healing, with 80% wound closure within seven days, which is encouraging," Dr. Kopecki said.

Dr Kopech, who is also a pediatric wound infection researcher at the Channel 7 Children's Research Foundation, said antibiotic treatments were becoming increasingly rare. "We urgently need to develop new non-antibiotic alternatives to treat and control wound infections. Black phosphorus seems to hit the mark, and we look forward to seeing this research translate into clinical treatments for chronic wounds," he said.

The team hopes to work with potential industry partners to develop and prototype the technology.