Bioinspired self-healing polypeptides

Recent research efforts have focused on developing soft, flexible, compliant materials for robotics, biointerfacing, and biosensing applications. Because of their intrinsic softness, these materials are susceptible to cut, puncture, scratch, and/or tear damage that compromise their physical integrity, and therefore self-healing properties are indispensable for soft machines and devices operating in dynamic environments. Here, we introduce self-assembled polypeptides that self-heal micro- and macro-scale mechanical damage within a second via reversible physical cross-linking. These proteins are systematically optimized to improve their hydrogen-bonded nanostructure and network morphology, with healing properties (~25 MPa strength after 1 second of healing) surpassing those found in other natural and synthetic soft materials by several orders of magnitude. Such healing performance opens new opportunities for bioinspired materials design, and addresses current limitations in self-healing materials for soft robotics and wearable technology.