Did You Know? Geckos Inspired New Medical Tape
On every continent except Antarctica, we can find species of small lizards called geckos. Many of the more than 1,000 different species of geckos are well known for their uniquely adhesivetoepads, allowing them to climb vertical surfaces like trees and walls. These toepads leave no sticky residue – unlike our common adhesive or medical tape – and can be reused over and over. By observing the structures of the toepads of geckos, researchers were able to create a synthetic adhesive tape that is reusable and leaves no residue, called gecko tape.
Gecko feet aren’t sticky, and they aren’t adhering to vertical surfaces like our normal tape. Instead, they have millions of microscopic hair-like structures called setae arranged in rows. Each setabranches off like tree branches into even more spatulae. When they touch a surface, each of those millions of spatulae creates a force of attraction called a van der Waals bond that, individually, areweak, but combined they keep the gecko in place. The row structure of the setae helps to easily detach from the surface in one direction. The longevity, reusability, and lack of residue are what drove researchers to attempt to make a new kind of adhesive using the same type of structure as a gecko’s foot.
Federally funded research to a number of researchers played a role in the development of gecko tape, and it isn’t just as of late. Dry gecko adhesives have been around since 2001 and have many different applications: moving large and heavy objects in construction, handling fragile materials like glass, and is even used by a robot to grasp surfaces at the International Space Station. But dry adhesives have limits; for example, they can’t adhere to tissue, work under water, or biodegrade, which are all important features for consideration in medical uses, such as surgery.
Recently, this has been gecko tape’s next venture for many researchers – to adapt dry gecko adhesive to replace sutures or staples for sealing wounds. This application would need to be compatible with tissue, sweat, oil, and other non-dry surfaces. Scientists have been successful. By taking this imitation of gecko toepads and applying a thin layer of a special polymer across the top of the spatulae, it creates a biocompatible and biodegradable bandage for wounds. These bandages don’t cause inflammation, and they dissolve over time – unlike sutures or staples that need to be removed – while adjusting to the body’s natural tissue as it heals. Many researchers are even working on infusing these adhesives with medications that are designed to be released over time throughout the healing process.
Biomimicry is a common theme in medical research, as well as science in general. By observing natural processes and behaviors, such as geckos climbing trees and walls, new ideas can be formed. Through curiosity-driven research, observing and adapting habits from the natural world can advance treatments and therapies for humans and lead to new medical breakthroughs.