Scientists from the University of Sydney have taken inspiration from carnivorous plants in order to develop new nanostructured surface coatings with anti-fouling properties, a study published in ACS Applied Materials & Interfaces reports.
Biofouling — which refers the build-up of dangerous biological material — is a large economic issue that costs the aquaculture and shipping industries billions of dollars each year in both maintenance and extra fuel usage. The issue has always been a problem, but it has gotten even worse since officials banned the anti-fouling agent tributyltin and created the need for new, non-toxic methods to stop marine biofouling.
To overcome that, the team in the study created new nanomaterials that prevents bacteria from growing on certain surfaces. The unique coating works through a series of ‘nanowrinkles’ that are inspired by the carnivorous Nepenthes pitcher plant, which traps a layer of water on the tiny structures around its opening to trap play.
As biofouling tends to occur on surfaces that are wet for extended periods of time, the slippery surface developed by the team stops bacteria from sticking on. That prevents the forming of biofilm, which then shuts down larger fouling process.
“We are keen to understand how these surfaces work and also push the boundaries of their application, especially for energy efficiency,” said study co-author Chiara Neto, an associate professor at the University of Sydney, according to Phys.org. “Slippery coatings are expected to be drag-reducing, which means that objects, such as ships, could move through water with much less energy required.”
Researchers tested the new materials by tying them to shark netting in Sydney’s Watson Bay. This showed that the slippery surfaces resisted almost all fouling from a common species of marine bacteria, while control Teflon samples that did not have the lubricating layer were completely fouled. In addition, the coatings are flexible and transparent, making them perfect for underwater cameras and sensors as well. The team hopes to continue developing the materials in order to find more applications for them in the future.