Study: Algae Defense Mechanism Foils Fouling
Marine antifouling coatings are designed specifically to do away with organisms like algae, but new research out of one German university shows how these coatings for ships and other marine structures could learn a thing or two from algae themselves.
A team of chemists at Johannes Gutenberg University Mainz has published research indicating that nanoparticles of cerium dioxide could play a vital role in a new generation of antifouling coatings, eliminating the need for copper-based biocides, which have been questioned because of potential harm to the environment.
The idea came from algae and sponges that use halogenated as a defense mechanism, the team says. Some of these organisms give off the compounds in order to stop what’s known as “quorum sensing”—a process by which other types of algae, biofilms or even barnacles sense one another and communicate. With quorum sensing stifled, the potentially invasive organisms are unable to form a colony.
"What is important is that it is effective not only under laboratory conditions but also when actually used in the aquatic environment," said researcher Karoline Herget.
The researchers, led by Karoline Herget, who wrote her doctoral thesis on the topic, found that nanoparticles of cerium dioxide—a common material that they say costs about the same as copper-based biocides—inhibit growth of these organisms on steel in the same way. Herget studied with Dr. Wolfgang Tremel of the Institute of Inorganic Chemistry and Analytical Chemistry at the school.
Cerium dioxide, they say, does not pose the same environmental risks as copper-based coatings, and doesn’t come with the potential for breeding resistant strains of organisms.
Effective in Real World Application
"What we have here is an environmentally compatible component of a new generation of antifouling coatings that simulate the natural defense systems employed by marine organisms. What is important is that it is effective not only under laboratory conditions but also when actually used in the aquatic environment," Herget said.
The new research, done in cooperation with BASF, was published in the journal Advanced Materials under the title “Haloperoxidase Mimicry by CeO2−x Nanorods Combats Biofouling.”