Ultra-thin nanotechnology could kill antibiotic resistant superbugs

Researchers have invented a nano-thin material that can slay superbugs that could be integrated into wound dressings and implants, helping to stave off infection.

The new black phosphorous-based nanotechnology has undergone advanced preclinical trials. It is effective against drug resistant bacteria, commonly referred to as superbugs, like Staphylococcus aureus or “golden staph.”

A team of researchers led by scientists and engineers at Melbourne’s RMIT University and the University of South Australia, detail their new material in a paper published in Advanced Therapeutics.

The results showed their treatment killed more than 99% of bacteria without damaging other cells in the biological models. It performed as well as an antibiotic in eliminating infection and accelerating healing. Wounds closed by 80% in 7 days.

“The beauty of our innovation is that it is not simply a coating – it can actually be integrated into common materials that devices are made of, as well as plastic and gels, to make them antimicrobial,” says co-lead researcher Professor Sumeet Walia from RMIT’s School of Engineering.

A previous RMIT-led study showed black phosphorous was effective at killing microbes when spread in nano-thin layers.

Black phosphorous is the most stable form of the mineral. Phosphorous occurs naturally in many foods. When in ultra-thin flakes, it degrades easily with oxygen, making it effective at killing microbes.

“As the nanomaterial breaks down, its surface reacts with the atmosphere to produce what are called reactive oxygen species,” Walia explains. “These species ultimately help by ripping bacterial cells apart.”

Superbugs, which have built up genetic resistance to common antibiotics, are a major global health threat. They cause about 700,000 deaths annually. Scientists believe this figure could balloon to 10 million deaths per year by 2050 if new antibacterial treatments are not developed.

The University of South Australia team showed how daily topical application of black phosphorous nanoflakes dramatically reduced infection.

“We urgently need to develop new alternative non-antibiotic approaches to treat and manage wound infection,” says Dr Zlatko Kopecki from the University of South Australia. “Black phosphorus seems to have hit the spot and we look forward to seeing the translation of this research towards clinical treatment of chronic wounds.”