Biology is inspiring an effort to create new materials that can repair themselves when damaged. According to experts, the first products with truly self-healing properties may be just around the corner. But it was a 2001 study led by Scott White from the University of Illinois at Urbana-Champaign, that really helped to kick-start the field. The group infused a plastic-like polymer with microscopic capsules containing a liquid healing agent. Cracking open the material caused the capsules to rupture, releasing the healing agent. When the agent made contact with a catalyst embedded in the material, a chemical reaction bonded the two faces of the crack together. The polymer recovered some 75% of its original toughness. In the last decade, the team has developed and refined its capsule-based systems, recently demonstrating an electrical circuit that healed itself when damaged. Microcapsules in the gold circuit released liquid metal in response to damage, swiftly restoring electrical conductivity, and bringing self-repairing electronic chips a step closer.