Better Antibiotic Coatings Against Biofilms

Researchers at the University of South Australia are working on making medical devices safer by developing a technique that will permanently bind antibacterial coatings to a polymer layer, thus preventing biofilms.

Biofilms are thin layers of bacterial colonies that can cover the surface of a medical device and expose a patient to infections.

These colonies can form on orthopedic implants, on catheters and even on contact lenses, and even if these devices have antibacterial materials on their surface, they never stick as well as they should.

The scientists working on the project are looking for a way of always having an antibacterial surface on a medical device, making it much safer.

After a serious research the scientists decided to use a plasma polymer coating, as it is a technique that works on different materials, including metal, glass and other polymers used in medical devices.

The plasma polymer coating is actually a very thin film that acts like a platform on which researchers can bind materials that either signal the bacteria not to attach by interfering with the cell's attachment mechanism or that do not allow multiplication once the bacteria are attached.

Hans Griesser of the University of South Australia said that “we believe that no solution will be universal so we want to establish an array of approaches.

“The new diterpene compounds that we are testing are structurally quite different from established antibacterial compounds, and they are effective against methicillin-resistant Staphylococcus aureus.

“That is what got us excited about them.”

This research was presented at the AVS 57th International Symposium & Exhibition, which takes place this week at the Albuquerque Convention Center in New Mexico.

For the presentation, the scientists compared different antibiotics applied to the polymer film, like silver nanoparticles, established antibiotic compounds and novel diterpene compounds derived from Australian plants that have been used in traditional medicine.

They said that every approach had arguments for and against which should be carefully weighted before passing on to implanting devices in the human body.