Remember the last time you stood at the edge of the ocean? Perhaps you climbed some rocky ledges and gazed into tidal pools or maybe you were standing on a pier. If you looked closely you may have seen barnacles or mussels stuck to whatever surfaces were available. Despite the ever-crashing waves, they were stuck, like glue.
Recently, a team from McGill University described how mussels achieve this adhesion.
The blue mussel (Mytilus edulis) uses an internally produced fluid protein and mixes it with iron and vanadium extracted from seawater. Within 2 to 3 minutes, the glue is useable by some of the mussel’s anatomical parts.
As you may know, mussels have beards. (If you ever cook mussels, you remove this part before cooking, or at least you should. It’s rather chewy otherwise.) These are made up of 50 to 100 fibrous byssal threads that keep the mussels tethered in place. At the end of each thread is a disc-shaped plaque that becomes the interface for applying the glue to the target surface.
This glue is strong enough to withstand the corrosive effects of saltwater. Consequently, understanding its composition and properties may lead to new products for applications such as surgical sutures. After all, the body is 70% water and rather salty.
Barnacles, on the other hand, may create a somewhat different type of glue. Their biochemistry was described in detail in 2019. Barnacles may have up to three different events in their lifecycle that contribute to their adhesive chemistry. It is so complex that I don’t feel qualified to summarize it here. A comprehensive overview is available at: https://www.frontiersin.org/articles/10.3389/fmars.2019.00565/full
Once again, nature offers more than one solution to the same sticky problem.
Unfortunately, the mussel glue academic paper is behind a paywall, but here is McGill’s press release: https://www.mcgill.ca/newsroom/channels/news/how-mussels-make-powerful-underwater-glue-333875
There is also a video of the mussels making the glue here: https://www.youtube.com/watch?v=1X5A0aZvRuI