Medical solutions inspired by biology
Industrial manufacturers are not the only ones turning to nature for inspiration. Medicine is also making advances in biomimetics. Shark skin is often used as a model due to the anti-fouling and drag-reduction properties of its structure. But that’s not all. Johannes Buchner, a professor of biotechnology at the Technical University of Munich, has begun studying the animal’s immune system.
Medical antibodies can be used to diagnose and treat cancer, but the organism quickly breaks them down. To deal with this problem, Mr. Buchner turned to nature to find robust antibodies. He needed a species distant enough from humans to have a different immune system. “500 million years separate us from the shark, and we found out that it has extremely resistant antibodies,” Buchner says.
After identifying the structures that give the shark’s antibodies their strength, the German research team was able to alter human antibodies to better resemble those of a shark.
Jaap den Toonder, a professor at the Institute for Complex Molecular Systems at the Eindhoven University of Technology, has been working to identify natural equivalents to engines and other pumps. He has found them in muscles and, at a molecular scale, in motor proteins such as dynein. “Motor proteins are responsible for the movement of muscle and cilia – long, thin structures measuring a few micrometres in length. They are everywhere and play a crucial role in the circulation of fluids (blood, urine, perspiration, etc.) in animals and plants.”
What is the researcher aiming for? Using these cilia to reproduce the anatomy and functions of organs in the style of microcircuits, creating “organs-on-chips” that can be used as experimental models or for medical analysis. Blood and sweat typically must be able to circulate in any experiment.
“Our devices are so small that flow has to be controlled on a scale of about 10 micrometres,” den Toonder says. “Current pumps are not precise enough.” Only bio-inspired cilia seem to be able to achieve such a feat.
Pioneers in biomimetics
The term was coined by American biophysicist Otto Schmitt in 1969. But imaginative humans were already looking to nature for inspiration long before that.
The Italian polymath Leonardo da Vinci studied the workings of birds’ wings and tried to translate those into artificial wings for man. His attempts failed due to the human body’s disproportionate weight compared to muscle power.
When the wind blows, a poppy capsule spreads its seeds evenly on the ground. Raoul Heinrich Francé, an Austro-Hungarian biologist, imitated its shape to design the perfect salt shaker. However, his shaker was never manufactured.
Cat’s eyes are a road safety device with reflective glass. Like the eyes of cats, they reflect the light that hits them, warning drivers at night of obstacles ahead, like construction sites. Their English inventor, Percy Shaw, was the first to apply this evolutionary characteristic of cats to new technology.
Today known under the brand name Velcro, the hook-and-loop fastener invented by Swiss engineer George de Mestral is perhaps the most famous example of biomimicry. It is inspired by the fastening mechanism of bur seeds, which catch on fur or clothing with their tiny elastic hooks.