A team of researchers at the University of Melbourne are developing nanoparticles that could potentially fight some of the most dangerous antibiotic resistant bacteria.
Antibacterial resistance
Led by associate professor Andrea O’Connor - a chemical engineer and deputy head of the University’s School of Chemical and Biomedical Engineering - the team has been working alongside researchers at the O’Brien Institute for almost 20 years.
Their work is focused on tissue engineering, the practice of merging polymer scaffolds to help regenerate tissue and organs. Whilst implanted materials will eventually degrade away, there is a risk of infection forming on the device whilst it is helping to enhance cell growth.
The two teams are focused on researching antimicrobial materials that can be used within the polymer devices to stop infections from bacteria occurring.
Speaking about the research, professor O’Connor says “it was partly triggered by a collaborator who came to my lab from the US, Dr Phong Tran, who’s now at Queensland University of Technology. He has a background working with nanoparticles, and so that expertise boosted our interest and activity in that area.”
The team have found that using the mineral selenium in the form of nanoparticles can stop the growth of bacteria.
The researchers believe that the nanoparticles stop bacteria growing by disrupting the membrane around the bacteria.
“One of the things that bacteria need to stay functioning is their cell membrane. If it starts to get holes in it or to leak, then the bacteria don’t function well and if it gets bad enough then they will die.
“One of the ways that these nanoparticles can attack bacteria is by disrupting that membrane so they make the bacteria leaky, and then things can pass in and out of the bacteria in a way they normally wouldn’t.” professor O’Connor said.
The team has tested the nanoparticles as a coating on the surface of medical implants as well as part of a tissue-engineering scaffold. The antimicrobial components are gradually released into their surroundings, helping to prevent infections forming.
Silver nanoparticles are currently used to prevent infections but need to be limited due to their toxicity. The researchers state that in contrast, selenium is safer for the human body.
The researchers have tested selenium-based nanoparticles against nine different types of bacteria and have found that it has been effective against all of them.
Speaking about where the team intends to use the nanoparticles, professor O’Connel said:
“One of the major areas that we’re interested in is that of chronic wounds. That’s a particular concern for patients with diabetes, and increases also with the prevalence of drug-resistant bacteria.
“It has potential for other applications as well. We’re interested in potential applications in the food industry, so we’re also developing materials to help limit food spoilage and the risk of food-borne infections.”
“The benefit of the nanoparticles that we’ve developed is they attack bacteria in multiple ways. It’s going to be difficult for the bacteria to develop resistance to all those different forms of attack.”