At the University of Kansas, some chemical engineers study petroleum, others work on solvents. Then there’s Professor Stevin Gehrke. He casts his scientific lens downward, looking for the future of medicine in things that scurry underfoot.
“What’s different about a bug that goes ‘squish’ when you step on it and a bug that goes ‘crunch’ when you step on it?” Gehrke describes his work.
Gehrke spends his time these days studying the structure of bugs for medical applications, but it’s not the kind of work he first set out to do. He’s a professor of chemical engineering at KU specializing in things like gelatin and control-release pill capsules. And he says he wasn’t thrilled when a K-State entomologist approached him about a collaboration over ten years ago.
“And he comes over to my office, and he actually has this big, green caterpillar that’s kind of crawling up his hand and up his arm," says Gehrke "And I’m sitting there, ‘I don’t want a caterpillar crawling up my arm!’”
Gehrke may not have been enthusiastic about working with bugs, but then he started studying them.
Meet The Red Flour Beetle
In a KU lab, Gehrke taps a few red flour beetles out of a glass jar. They’re tiny. Just about an eighth of an inch long. A small collection of beetles like these spend their days at KU eating their fill of flour or oatmeal. Until they meet graduate student Tricia Sprouse.
“Basically, Tricia went to grad school to get her Ph.D on pulling wings off of beetles," Gehrke says.
For a recent project, they tested the structure of the beetles with what looks like a huge drill press. It pushes and pulls materials like plastic or rubber to measure how much force they can take. This is how Gehrke found out something amazing about the hard covering over the back of beetles’ wings.
He explains that the strength of this insect body part is "about a hundred times greater than the synthetic gels that are widely used.”
It’s not the material but the structure that makes beetle skeletons way stronger than similar synthetics. That structure, along with a lack of water in their bodies, is what give the beetles their crunch.
But how can this be applied to medicine?
From Beetles To Cartilage
One of the more promising ideas is cartilage replacements, a procedure that Gehrke believe could be huge, especially for people who have osteoarthritis. The disease effects around 21 million people in the United States, and it degenerates cartilage along with bone.
But there currently is no treatment beyond pain relief.
“Cartilage is a tissue in the body that doesn’t heal very well," explains Gehrke.
Gehrke believes they can help cartilage heal by using a super-strong beetle-inspired synthetic material as a kind of scaffolding. Say you have an injury and need new cartilage in part of your knee. Gehrke proposes filling in the space with a mix of cartilage-producing cells and a beetle-inspired synthetic. The synthetic holds the space open, like a scaffolding, so the cartilage can grow. After a few weeks, when the cartilage has filled into the space, the synthetic disintegrates, like a time-release pill capsule.
“That’s the vision," says Gehrke.
Gehrke recently received a third grant from the National Science Foundation for his work. He’s also received funding from groups like the National Institutes for Health.
Professor Gehrke has been working with bug for a while now, and its changed his relationship with them.
“I sometimes tell my kids if they’re complaining about – you know, insects have gotten in the house. I say ‘Well, that helps pay for your food and clothing and so on,'” says Gehrke with a laugh.
The beetles and other insects will keep Gehrke busy for a while. He estimates it could be five to ten years before the cartilage treatment is available.