Physics Buzz

Try sticking a Band-Aid to wet skin and you'll quickly realize that everyday glues are no match for wet surfaces. Mussels, on the other hand, are masters of holding fast to wet rocks, piers, and even to each other. Researchers at the University of California, Santa Barbara are studying these aquatic creatures to understand what makes them so sticky and hopefully use them as inspiration for creating synthetic wet adhesives. Mussel with byssus threads and disk-like plaques binding it to the rock. Credit: Brocken Inaglory via Wikimedia commons "The mussel foot protein is the champion of adhesion in the animal world," said Emmanouela Filippidi , a postdoctoral researcher at UC Santa Barbara, in a press conference yesterday at the APS March Meeting . She said individual proteins have an adhesion strength of 15 mJ/m 2 , which describes the amount of energy per unit area that they can withstand, and is only a few times smaller than our best man-made

Gecko / Image credit: Chris Hunkeler It is almost impossible to read about van der Waals forces in a science textbook without also reading about geckos’ feet . In general, van der Waals forces are the attractive and repulsive forces between two dipole molecules. Gecko feet are padded with microscopic fibers, which adhere to surfaces through van der Waals interactions. These fibers allow geckos to climb smooth surfaces like glass. Scientists at the Department of Mechanical Engineering at the University of California Santa Barbara have successfully made a reusable dry adhesive inspired by the gecko’s feet. The results were published on January 14, 2013 in the IOP journal Smart Materials and Structures . Gecko toes / Image Credit: Matt Reinbold “We’ve been working a problem of this type...for about seven or eight years,” said Kimberly Turner, a professor of mechanical engineering and lead researcher on the paper. “I’m really interested in how nature has been able to achieve