Forget `Strong As Steel.' Here Comes Spider Silk

Someday, the fibers that a spider uses to spin its web could find their way into a soldier's flak vest. According to Christopher Viney, an assistant professor of bioengineering at the University of Washington in Seattle, spider silk is stronger than steel and 10 times tougher than any other material. If researchers could synthesize spider silk, it could help fashion suspension bridges or flak helmets.

Viney's goal is to duplicate the spider's silkmaking process for industrial use. Spiders make silk from a protein solution dissolved in water inside their bodies. So far, the gene for the protein has been isolated and spliced into bacteria that churn out vats of the stuff. But humans must use caustic chemicals and high temperatures to spin their silk. And the resulting fibers are still weaker than natural silk. Viney recently found one key to silk's strength: The protein solution temporarily becomes a liquid crystal after it is secreted by spiders. Still, he says, it could take five years to match nature's best weavers.