Researchers from the University of Nottingham have discovered that microscopic patterns etched into plastic surfaces can dramatically reduce bacterial growth — offering a promising new way to prevent infections on medical devices like catheters and breathing tubes.
The research, published in Nature Communications, shows that certain textured patterns disrupt the bacteria’s ability to form biofilms — slimy layers of bacteria that stick to surfaces protecting the microbes from antibiotics and the immune system.
Disrupting the formation of biofilms means infections can be stopped before they take hold, and the immune system is better able to clear out any lingering bacteria.
Instead of using antimicrobial coatings in the materials used — which can promote antibiotic resistance — the team explored whether simply changing the surface shape of the plastic could make it inhospitable to microbes.
They screened over 2000 surface patterns on various plastics, including polyurethane, a material commonly used in medical devices.
On the best-performing designs, bacteria were lured into tiny crevices and tricked into producing a lubricant. This response stopped them from sticking to the surface in the first place, which blocked biofilm formation and made them easier for the body’s immune system to eliminate.
“Previous research has shown that introducing antibiotics to medical devices has flaws, such as driving the development of antibiotic resistance,” says lead author Professor Paul Williams, an expert in molecular microbiology. “Our study took this idea one step further as we wanted to find out if we could create a simple landscape on a catheter, made of the same material that bacteria didn’t like and couldn’t form biofilms on.”
Because there were thousands of surface designs to test, the team used machine learning — an artificial intelligence technique — to spot which patterns were most effective at stopping bacterial growth.
The approach could be commercialised relatively easily, since it doesn’t require changes to the materials already used in existing devices.
“Using physically patterned surfaces has the advantage over coating approaches that it can be applied to existing device materials, reducing the barrier to commercial application. Our discovery could save the NHS a lot of money,” says Williams.