Scientists already know that the tiny hairs on geckos’ toe pads enable them to cling, like Velcro, to vertical surfaces. Now, University of Akron researchers are unfolding clues to the reptiles’ gripping power in wet conditions in order to create a synthetic adhesive that sticks when moist or on wet surfaces.
Place a single water droplet on the sole of a gecko toe, and the pad repels the water. The anti-wetting property helps explain how geckos maneuver in rainy tropical conditions. However, saturate that same toe pad in water or drench the surface on which it climbs, and adhesion slips away, the researchers say.
The research team members tested gecko toe hair adhesion in a series of scenarios: dry toe pads on dry, misted and wet surfaces and soaked toe pads on dry, misted and wet glass. The soaked toe pads demonstrated low to no adhesion proportionately with the wetness of the surface on which they were applied and pulled. Likewise, dry toe pads lost their adhesive grip increasingly with the amount of water applied to the surface upon which they were pulled. For the experiments, geckos were pulled on a glass surface by way of a small, gentle harness placed around their midsections.
After close study of the tiny hairs at the bottom of gecko feet that enable them to cling to surfaces, the team have already developed a dry synthetic adhesive, comprised of carbon nanotubes, that outperforms nature’s variety. Now, with these new findings, Dhinojwala and his colleagues are one step closer to unfolding the secrets behind gecko toe adhesion in wetness.
This story is reprinted from material from The University of Akron, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.