A technique to permanently bind antibacterial coatings to medical devices has been developed by a research group at the University of South Australia. The technique can find application in orthopedic implants, catheters, contact lenses; first binding them to a polymer layer. The overall approach is aimed at preventing biofilm formation on implants, which can increase the risk of infection. This technique works on different base materials, including glass, metal and many polymers used in manufacturing devices, according to the release. The team started by applying a plasma polymer coating, which is an ultra-thin film. The ultra-thin polymer film acts as a scaffold that materials bind to and either signal the bacteria to not attach to the surface or prevent the bacteria from multiplying once they are attached to it.
For this purpose, the new diterpene compounds being tested by the team are structurally quite different from established antibacterial compounds, and they are effective against methicillin-resistant Staphylococcus aureus. The team discussed and compared how several antibiotics work when they were applied to the polymer film, including silver nanoparticles and novel diterpene compounds. The latter are derived from Australian plants used in traditional medicine. Each approach has its pros and cons, which must be carefully weighed before ever using them on devices implanted in humans.