Jon Wilker is fascinated with mussels and oysters. Not because he likes to eat them particularly, but for their stickiness, which is unique in the natural world. “Before I moved to Indiana, I did a lot of scuba diving. I would see all these creatures on rocks, and I just wondered how they did it,” he says.
That was 13 years ago. Wilker, a chemistry professor at Purdue University, has since become a world expert on the adhesiveness of certain shellfish. “I looked into it, and I found there wasn’t as much information as you might think,” he adds.
Wilker studies the “glues” that mussels, oysters, and other animals use to stick to rocks, then tries to reproduce those substances in synthetic form. That’s significant for two reasons. One, these nature-informed adhesives are non-toxic, unlike most oil-derived glues. And, two, they “set wet”–that is, they adhere even in watery environments like the human body. Wilker’s adhesives potentially could be used to glue bones back together or fix skin on your arm or back or any number of bodily applications. There’s nothing like these bio-glues on the market today.
At first, Wilker thought of farming or milking glue from mussels or similar creatures. But he says that isn’t very practical. Each animal only produces a small amount (about 25 milligrams) for a lot of effort. And, by using a live substance, purity is an issue as is the possibility of a human immune response that would dull the glue’s effectiveness.
Instead, he’s working to swap in animal-like proteins into existing materials. “What we’re doing is taking the polymers that are in plastic and every now and then we incorporate some of the chemistry that the proteins have in the animals. The proteins are very unusual,” he says.
For example, his lab took everyday polystyrene and put some mussel chemistry into it. The result was a substance as strong as Super Glue. “It’s a very conspicuous change in the properties, and the nice thing about polystyrene is it’s something you can make at train-car scale,” he says.
Wilker has also worked on glueing bones together (using another adhesive) and patching pig skin (see the photo above). Potentially, the glues could be used by surgeons instead of sutures and limb bolts (see the video above from a recent PopTech event), limiting the damage that happens you use those techniques.
Then, there are possible applications in aircraft and auto manufacturing (reducing the need for riveting), dentistry (instead of dental cement), wood formation like plywood (which now uses formaldehyde, a toxic substance), and even cosmetics. Wilker regularly hears from companies wanting to adopt his work. One of his favorite inquiries was a company that makes artificial eyelashes. Today, they basically use Super Glue.
Wilker has an infectiously positive attitude. You really want him to succeed in commercializing his work, especially if it could improve surgery, cut the use of formaldehyde in the environment, and reduce the weight of planes and cars. He’s open to forming a startup or collaborating with industry, but he’s not in a hurry. He wants to perfect his adhesives first.
“It’s easy to beat what’s available now. Before commercializing, I want to get [the glues] really, really strong,” he says. “If you put two pieces of bone together and pull them apart, the bone should break before the bond does. That’s when we’ll start looking for investment money. We’re not there yet–but we do have things sticking.”