Spider power

27 April 2004

BREMEN – Research into how spiders stick to almost any surface could lead to innovative adhesive technology.

Scientists have found that jumping spiders are capable of carrying over 170 times their own body weight while clinging upside down.

In the first research of its kind, the team from Switzerland and Germany examined the jumping spider’s “foot” to find out how the creature managed to stick to almost any surface.

Their research, published in Britain’s Institute of Physics journal Smart Materials and Structures, shows that the “van der Waals” adhesive force is behind the spiders’ sticking power.

That same adhesive force could be harnessed to create spacesuits which would stick to the walls of a spacecraft.

Professor Antonia Kesel, head of the Bremen-based research group, said: “One possible application of our research would be to develop Post-it notes based on the van der Waals force, which would stick even if they got wet or greasy.

“You could also imagine astronauts using spacesuits that help them stick to the walls of a spacecraft – just like a spider on the ceiling.”

Scientists used a special microscope to make images of the jumping spider’s foot. Tiny hairs called setules which stick to another tuft of hair on the bottom of the spider’s leg are what holds the creature onto the underlying surface.

The van der Waals force acts between individual molecules that are within a nanometre of each other – about 10,000 times more narrow than the width of a human hair.

Unusually, this adhesive force is not affected by its surrounding environment.

Kesel said: “We carried out this research to find out how these spiders have evolved to stick to surfaces, and found that it was all down to a microscopic force between molecules. We now hope that this basic research will lead the way to new and innovative technology.”

DPA

Subject: German news