Once bacteria cling, it can sometimes be hard to make them let go as they accumulate and form adhesive biofilms. That's a particular problem on medical materials use for implants and instruments – but a new non-stick material might change things.
A team of researchers form Harvard has developed a powerfully non-stick material that can be used as a medical material that prevent the build up of biofilms – in turn also preventing the infections they can cause. The new material uses polymers that are infused with liquids that are naturally lubricating.
Large polymer molecules can soak up large quantities of these liquids, acting like sponges that then slowly release the lubricant, making the material's surface slippery and repellant. The researchers have infused solid silicone polymers – already used in medical situations – and saturated it with silicone oil. Both are non-toxic and perfectly harmless inside the human body, but result in a coating that prevents bacteria clinging to it, stopping the creation the of biofilms.
In experiments, tubing made form the infused silicone was shown to resist Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus epidermidis – all common bacteria that regularly form biofilms and cause urinary, tissue and blood infections.
The infusion of oil into the material makes the slippery surface extremely robust. In fact, the researchers claim that it could even withstand conventional sterilisation methods, making it perfect for long-lasting applications. If the surface oil is pulled away, it's simply replenished by more from within the polymer.
"With widespread antibiotic resistance cropping up in many strains of infection-causing bacteria, developing out-of-the-box strategies to protect patients from bacterial biofilms has become a critical focus area for clinical researchers," explains Donald Ingber, who was involved in the research. "Liquid-infused polymers could be used to prevent biofilms from ever taking hold." [ACS Biomaterials Science and Engineering, Harvard]
Image by Juho Mattila under Creative Commons licence