Researchers at Australia's University of New South Wales (UNSW) have come up with a new way of tackling harmful biofilms. The non-toxic method, which combines targeted nanoparticles with heat, could have a wide range of applications.

When bacteria exist as single, independent cells they're usually easy to treat using antibiotics. However, given enough time, bacteria will often band together to form a biofilm, growing into a matrix that's much more difficult to treat.

As many as 80 percent of infections are linked to biofilms, and they can also infect equipment such as dialysis catheters, making them a persistent and growing problem in hospitals across the globe.

Looking for new ways to tackle the issue, the UNSW researchers made a breakthrough when working with the human pathogen Pseudomonas aeruginosa – an organism that serves as a model of how most other bacteria react to the treatment.

In order to attack the biofilm, the team attempted to recreate what happens to the cells when they move to colonize a new site. When this occurs, the structure breaks up into individual cells, making them more susceptible to attack.

To do so, the team injected iron oxide nanoparticles and heated them with an applied magnetic field. This raised the temperature by 5 °C, inducing local hyperthermia and, as hoped, caused the biofilm cells to disperse. Once the matrix of cell was broken up, the bacteria became much easier to treat.

"The use of these polymer-coated iron oxide nanoparticles to disperse biofilms may have broad applications across a range of clinical and industrial settings," says study lead Professor Cyrille Boyer. "Once dispersed, the bacteria are easier to deal with – creating the potenial to remove recalcitrant, antimicrobial-tolerant biofilm infections."

The findings were published in the journal Scientific Reports.

Source: UNSW