A gel made of a protein found in human cells can capture particles travelling at supersonic speeds without destroying them on impact, suggesting the material could be used in body armour or for collecting space debris.
Our cells contain a protein called talin that helps them sense and navigate their local environment in the body by changing structure in response to external forces. and his colleagues at the University of Kent, UK, have made a talin-based gel that reforms after it is struck by a projectile, allowing the object to be removed unharmed.
鈥淓ach talin molecule has 13 鈥榮witches鈥� that can unfold when force is applied and these re-fold after force is removed, enabling shock absorption,鈥� says Goult.
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The team adapted the ends of three talin switches, then linked these modified molecules together using water and a gelling agent to form a mesh-like structure.
When something hits the gel, the energy unfolds the modified talin switches rather than being converted to heat, as is the case with existing materials, says Goult. Silica gels filled with air, or aerogels, have previously been used to capture small objects in space, but these heat up on impact, potentially damaging both themselves and the captured material.
To test their creation, the researchers used a piston to fire particles of basalt, which were between 20 and 70 micrometres wide, at a sample of the gel in front of an aluminium plate. Even when firing the particles at supersonic speeds of 1.5 kilometres per second, the gel prevented them from reaching the plate.
The same particles completely destroyed a control gel made of polyvinylpyrrolidone, which is used in contact lenses and bone implants, and left 1.33-millimetre-wide craters in the aluminium plate.
When the researchers removed the basalt particles from the talin-based gel, they found the projectiles鈥� structure was completely preserved. 鈥淥ur material perfectly caught and 鈥榗uddled鈥� with the projectile鈥� keeping it beautifully preserved,鈥� says team member .
The researchers are now working with a company to develop the gel as a component of body armour. As other proteins labelled with fluorescent markers can bind to talin in its unfolded state, damage to the armour could be identified by adding fluorescent proteins to the gel, says Goult.
搁别蹿别谤别苍肠别:听bioRxiv,
