Just add titanium for 'super-tough' spider silk
London, May 2 (ANI): A team of scientists has determined that by adding the metal titanium, spider silk can be made super tough, in fact 10 times as hard to snap.
The team included Seung-Mo Lee and Mato Knez at the Max Planck Institute of Microstructure Physics in Halle, Germany.
The scientists fired beams of ionised metal compounds at lengths of silk from the orb-weaving spider Araneus diatematus using a technology called atomic layer deposition (ALD).
As well as coating each silk fibre in a fine metal oxide, some metal ions penetrated the fibre.
They tried zinc, aluminium and titanium compounds, all of which improved the mechanical properties of the silk.
"With all three metals, the fibres can hold three to four times as much weight," said Knez.he fibres also become stretchier, so that their toughness - the energy needed to break a strand - rises even more.
"The work needed to break the fibre rises tenfold with titanium, ninefold with aluminium and fivefold with zinc," said Knez.
The team believes that the metals are reacting with the spider silk's protein structure, forming strong covalently bonded cross-links between the amino acid polymers within the silk.
Normally, these polymers are only linked by weaker hydrogen bonds.
Spider silk is not a practical engineering material, but materials scientists are trying to produce artificial fibres that mimic its properties.
If they succeed, the result could be super-tough textiles.
According to Knez, the technique has more immediate potential for toughening other biomaterials such as collagen.
"Mechanically improving collagen using our technique might open several new possible applications, like artificial tendons," he said. (ANI)