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This is scientific American’s 60-Sencond Science. I am Karen Hopkin. This will just take a minute.

When you think about silk, you probably think of gossamer¹ fibers³ woven into lustrous⁴ garments or decadently⁵ 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 jaws⁶, claws, and stingers. So the scientists got to wondering whether they could take a similar tactic⁷ to make silk even stronger. Such reinforced fibers could prove useful for making really sturdy medical devices, like surgical⁸ sutures, or even artificial tissues like bone or tendon or even arteries⁹.

The scientists used a process called atomic layer deposition¹⁰ to coat some spider silk with zinc¹¹, titanium or aluminum¹². In addition to covering the outside of the silk, some of the metals seeped¹³ into the material, incorporating into the structure of the fiber². 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 adage¹⁴ almost goes, O, what a stronger web we weave, when bits of metal to the silk we cleave¹⁵.

Thanks for the minute. For  Scientific American’s 60-Sencond Science. I am Karen Hopkin.