Science 324, 488–492 (2009)

Spider silk is naturally tougher than steel, but adding metal makes it stronger still.

Seung-Mo Lee and Mato Knez of the Max Planck Institute of Microstructure Physics in Halle, Germany, and their colleagues took dragline silks from a spider caught in the institute gardens and pulsed them with metals in a process called multiple pulsed vapour-phase infiltration. Zinc oxide, titanium oxide or aluminium oxide not only coated the silk but also infiltrated the protein structure, resulting in much higher strength and extensibility.

The technique could be used on other biomaterials, the researchers say, such as collagen membranes from eggs.