Scientists at Dublin City University have found a way to stop marine organisms attaching themselves to ships and other ocean infrastructure.
And they owe it all to a wonderful little flatfish appropriately called Brill.
Microorganisms in the sea are attracted to handy surfaces such as ship hulls, propellers, buoys and energy platforms. Once attached, they combine to form a slimy coating that can be a mix of algae, larvae and tiny worms that in turn attracts larger creatures such as barnacles and mussels which build up in layers, slowing down ships, obstructing sensory instruments and hampering equipment.
The coating created by the microorganisms is called biofilm and the trouble it causes is termed biofouling. Various paints have been developed to try to make surfaces unattractive for attachment but with limited success. A research team at DCU, however, have taken inspiration from Brill, a flatfish that spends much of its time motionless on the seabed yet doesn’t become laden with microorganisms.
The scales pattern of the Brill fish will be used. Photo: Getty Images.
Professor Fiona Regan who led the research team said Brill was found to have a particular texture on its scales, with microscopic spacings that prevent biofilm development. They have managed to replicate the technique in the DCU labs and now want to move to the next phase of the project.
“Our work has discovered that these brill-inspired micro textures cause a disruption to the formation of a biofilm leading to surfaces that are easier to clean or have a slower rate of biofilm formation,” Prof Regan said.
“We would hope to investigate being able to generate these textures at scale for application to large surfaces.
“These factors are important for future developments of ocean energy blades, boats, and buoys that become so impacted by natural biological growth that there is a huge cost for its removal.”
Their work, featured in the current edition of the scientific journal, Science of the Total Environment, began several years ago when they immersed structures of different metals and coatings in the waters of Dublin Port. They compared the resulting growth, finding that structures made of copper were a good natural deterrent but everything else eventually got covered. Their journal paper points out that chemical paints developed from the 1960s were effective but their use was restricted soon after and then phased out because of concerns they were poisonous to marine life.
After the Dublin Port experiments, the team decided to explore ‘bioinspired design’ – looking at how nature manages the problem. Brill have deceptively smooth skin but its scales actually have microscopic peaks and recesses that seem to be the exact dimensions, arranged in the perfect pattern, to prevent microorganisms gaining sufficient foothold to create a biofilm.
Prof Regan said the manmade material mimicking the brill scales was designed to be used on all underwater devices, which could be vital when Ireland begins building offshore wind farms in the coming years.
“The conditions of biofouling are different for static cables compared with infrastructure that moves or rotates,” she cautioned.
“The work demonstrates, though, potential for a new way of protecting underway systems.”