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Mussels may be popular among seafood lovers, but many boaters consider them pests. They colonize the bottoms of ships, plug the water pipes and stick to the engines.
For the chemical engineers, however, these very properties make the molds wonderful. They can stick to just about any surface, and under water, no less. The study of practical applications of mussel biology is so widespread that there is a special term: mold-inspired chemistry.
And now, researchers believe that studying how mussels stick to food can help them combat water pollution, according to a recent mussel-inspired chemistry report published this week in the newspaper. Matter. Although most of the technologies studied are not yet widely applicable, research in the field of water cleaning inspired by mussels is very promising, says the review.
The World Economic Forum considers that lack of access to clean water is one of the greatest societal risks facing the planet today. And access to water will only worsen as the climate changes, populations increase and industrial production increases. Scientists have therefore tried to find effective methods of cleaning water by analyzing its interactions with solid materials, such as membranes and sorbents (oil-absorbing materials).
The sticky nature of mussels is a study material of choice for those who are interested in cleaning the water. This involves a chemical interaction between the substances that makes them adhere even under water, which is usually very difficult to do, says J. Herbert Waite, Distinguished Professor of the University of California at Santa Barbara, who studies the biochemistry of marine organisms.
"It's intuitive for most people that, if you try to stick things, you do not even try to do it under water," says Waite. "The main reason is that water, as a molecule, likes to adhere to surfaces more and better than most glues." By studying how mussels are able to create a sticky effect under the sea, engineers can better understand how surfaces interact with substances in the water and create materials that can help separate water from contaminants.
The sticky nature of mussels works as follows: they bind to surfaces using strands called byssus wires, which escape from their shell like wild and sticky beard hair. Each wire contains a group of amino acids called DOPA, which helps it to bind to almost all underwater surfaces.
The engineers were able to mimic the DOPA produced by the mussels by taking dopamine (yeah, this dopamine – which plays a role in the reward circuit of our brain) and using it to synthesize a chemical called polydopamine, or PDA . And PDA can be turned into an adhesive similar to that of the byssus wires of a mold.
You can do a lot of things with water and a PDA. For example, an emerging area of research that Darling and his colleagues have explored is using a PDA to create an interface that repels charged particles and attracts water. This technology could help us clean wastewater polluted by heavy metals. Other groups work on membranes that attract oil but repel water, a technology that could be useful in dealing with oil spills.
"If you apply an oil-water mixture on this membrane, the oil will spontaneously pass through the pores and the water will stay behind," says Seth Darling, director of the Center for Molecular Engineering at the National Laboratory of Microbiology. Argonne and co-author of the study. . (To date, this technology is only used on small simulated oil spills, he explains).
Blair Brettmann, a chemical engineer and assistant professor at Georgia Tech who did not participate in the study, says the review highlights interesting developments for water cleaning.
"There are so many things you can do with [these materials] – it's nice to see them being applied [to this area], "she says.Brettmann says that she usually sees materials inspired molds used as medical adhesives in humid environments.
Brettmann and Darling agree that these materials need to become more effective before they can be used.
Darling and his colleagues are excited about the challenges faced by mussel-inspired chemistry – he adds that the fact that mussels are hard to learn is much more. For example, their membership might work so well because they collaborate as colonies and combine different amino acids to improve stickiness.
"Often, Mother Nature is smarter than us, [because] She has had billions of years to find solutions, "Darling said. We are still learning mussels. "
Susie Neilson is an intern at NPR's Science Desk. Follow her on Twitter here: @susieneilson.