This blog entry is another of our "Science in the News” articles. Feel free to print it out and share it with your students, or to have one of your students present the information to the rest of the class—after all, one of the most important parts of science is learning to communicate information.
This entry is part of a short series about the work of Andre Geim, the 2010 Nobel Prize winner for physics. This entry details some of his other work. Be sure to join us next time to read about his Nobel work, too.
Andre Geim and Gecko Tape
Andre Geim likes to play with science. He is a physicist and nanotechnologist at the University of Manchester in England. When he heard that other scientists had discovered how geckos stick to walls and ceilings he decided to create adhesive tape that used the same principle.
Gecko feet are covered with little ridges. This picture shows a gecko foot stuck to a plane of glass.
Photo by Bjørn Christian Tørrissen
The ridges on the toes are called lamella, and are made up of rows of hair-like structures called setae (approximately 200,000 setae per toe.) Each seta has hundreds to thousands of tiny projecting flaps called spatulae.
Because the toes, lamellar ridges, setal hairs, and spatula flaps are all soft and flexible, the spatulae can spread out and touch the surfaces that a gecko is walking on. Molecules that are close to each other are slightly attracted to each other, a little like very small, very weak magnets. But because there are so many spatula touching molecules on the gecko’s walking surface, the total effect is like many, many, many tiny magnets—enough to allow the gecko to stick to walls, ceilings, glass, or pretty much anything else (except teflon!)
Professor Geim and his colleagues created a small piece of sticky tape using technology similar to that used to make computer chips. The "tape” is made of tiny plastic pillars (about two microns tall) that are regularly spaced on a flexible base. A micron is VERY small—about a thousandth of a millimeter!
Here is a picture of the tiny pillars:
Used by the associated press by permission of Professor Geim
To test whether the tape worked, Professor Geim put a small piece of it on a toy spiderman’s hand and tried to see whether the spider man toy would stick to a plane of glass. As you can see, it did!
"Test of gecko tape,” by Geim and colleagues, from "Microfabricated adhesive mimicking gecko foot-hair"
Although gecko tape is pretty cool, it isn’t time yet to run out and buy your own. So far only a small amount of tape (a couple of square centimeters) has been created. Right now the tape-creation process is very time-consuming and very expensive, and the researchers have some kinks to work out, but their calculations indicate that if they made enough gecko tape to cover a human hand (about 200 square centimeters) the tape would be able to suspend a whole HUMAN from the ceiling—maybe even spider man himself!
You just never know what might happen when smart kids or scientists start to play with science ideas—AMAZING!