[The following is an exact transcript of this podcast.]

When you think about silk, you probably think of gossamer fibers woven into lustrous garments or decadently soft bedsheets. But silk is also prized for its strength. Mechanically speaking, silk fibers are as tough as steel. But in the April 24th issue of Science, German researchers report that a dusting of metal makes silk even tougher.

In nature, lots of insects and animals use a touch of metal to harden body parts such as jaws, claws, and stingers. So the scientists got to wondering whether they could take a similar tactic to make silk even stronger. Such reinforced fibers could prove useful for making really sturdy medical devices, like surgical sutures, or even artificial tissues like bone or tendon or even arteries.

The scientists used a process called atomic layer deposition to coat some spider silk with zinc, titanium or aluminum. In addition to covering the outside of the silk, some of the metals seeped into the material, incorporating into the structure of the fiber. And, it will probably come as no surprise that the fibers infused with titanium or zinc or aluminum are much harder to break than Original Recipe silk. As the old adage almost goes, O, what a stronger web we weave, when bits of metal to the silk we cleave.

—Karen Hopkin