Scientists from Lewis and Clark
College, working collaboratively with
the Joint School of Nanoscience and Nanoengineering (JSNN) in the United States
have examined the fascinating climbing skills of geckos and spiders using the
ORION helium ion microscope from Carl Zeiss. High-resolution images displaying
unique definition and detail rendition reveal even the finest structures on the
feet of these animals. This imaging advances the understanding of how the
masterful climbing skills of these creatures are attributed to adhesive forces
or, in other words, intermolecular attractions. The secret lies in the fine
structure of the tiny hairs, or “setae,” that cover the undersides of
the feet. The spatula-shaped tips of the hairs allow the creatures to make a vast
number of contacts on the surface. The simple adhesive force enables the gecko
or spider to carry many times its own weight when climbing upside down.
Until now, it was extremely difficult to obtain
images of the tiny, delicate hairs. Electron microscopes generate an
electrostatic charge on the surface of practically all biological specimens.
This impairs the image quality, which is why research scientists frequently
cover biological specimens with a thin gold coating during preparation. This,
in turn, masks the fine structures of the gecko and spider hairs. Helium ion
microscopy offers a simple but effective solution to this problem; static
charge is neutralized in a very straightforward manner, allowing the specimen
to be imaged in its natural state. The result is razor-sharp images that offer
not only detailed scientific content, but also an outstanding degree of
abstract beauty.
Carl Zeiss
Microscopy, www.zeiss.com/micro
