Can electronics heal themselves?

When someone gets a cut, white blood cells follow chemical signals to the site of the injury, fending off infection and promoting healing. Meanwhile, platelets rapidly crowd in to stop the bleeding. Collagen fills the wound.A scanning electron microscope image captures spherical nanomotors migrating to a crack in order to restore conductivity. Image courtesy of Jinxing Li (University of California, San Diego, La Jolla, CA).If electronic materials could heal themselves like living tissues, scars on all sorts of devices would fade. There would be fewer cracked cell phone screens. Self-healing electronic materials could boost the durability of wearable electronics. And electronics for distributed environmental and urban sensors, as well as implanted medical devices, could be refurbished autonomously, mitigating the need for difficult, risky, and costly replacements.But if researchers are to invent myriad efficient, effective ways to allow electronics to heal themselves, a multitude of scientific and technical challenges must be addressed. Scientists have, for example, made scratch-resistant paints and crack-healing concrete coatings by mixing in capsules full of healing glues. But anything added to or released into an electronic circuit has to have the right electronic properties or it will impair performance even as it heals the physical crack. To get around these challenges and devise smart self-healing, some investigators are looking back to biology for inspiration.That’s precisely the strategy of chemical engineer Anna Balazs at the University of Pittsburgh. Balazs is attempting to build an artificial white blood cell to monitor and fix flaws in electronic materials; it would sense scratches …