Metallic Spider Silk Five Times Stronger than Steel

Scientists have discovered a way to make spider silk three times stronger by adding small amounts of metal. Even though the natural spider-made fiber is already tougher and lighter than steel, this new technique could make it useful for manufacturing super-tough textiles and high-tech medical materials, such as artificial bones and tendons.

The discovery, published by the journal Science, was made by researcher Seung-Mo Lee of the Max Planck Institute of Microstructure Physics in Halle, Germany. Lee and his colleagues used a process called atomic layer deposition, which not only coated spider dragline silks with metal but also caused some metal ions to penetrate the fibers and react with their protein structure.

The breakthrough addition of zinc, titanium or aluminum to a length of spider silk made it more resistant to breaking or deforming, effectively making the strand three times stronger. The discovery was based on the observation that some insects show traces of metals in the toughest parts of their body parts. The jaws of leaf-cutter ants and locusts, for example, both contain high levels of zinc, making them particularly stiff and hard.

“This new discovery is absolutely incredible,” stated Kraig Biocraft Laboratories CEO Kim Thompson. “Spider silk is already known as one of the strongest fibers found in nature and is recognized for its unparalleled capacity to absorb and dissipate energy in a very controlled manner. Being five times stronger than steel of the same diameter in its natural form, this enhancement reminds us again of the extraordinary potential spider silk has. Kraig Biocraft Laboratories is committed to continuing to develop sustainable spider silk for commercial use worldwide.”