Fully degradable, highly elastomeric and adhesive silk fibroin electronic skin for microdynamic pressure monitoring

Highly sensitive soft electronic devices with biocompatibility are essential for epidermis and implantable applications. Inspired by the mussel adhesion mechanism, we report a silk fibroin (SF) elastomer with good adhesion, which can adhere tightly to the skin and monitor tiny vibration signals of the human body in real time. A mussel-inspired redox environment is created in SF networks by doping polydopamine (PDA)-intercalated clay, which for the first time endows SF elastomers with strong adhesion to various materials. Moreover, the introduction of PDA-clay allows the SF network to reconfigure at the mesoscopic scale and controls its nucleation rate, thus reducing the modulus and improving the flexibility of the elastomer, satisfying the requirements of skin conformal, and greatly improving the device sensitivity. Considering the biodegradable and biocompatible features, this elastomer can find potential applications in epidermis or implantable health-monitoring devices, e.g., speech recognition and pulse diagnosis are demonstrated with the assistance of deep learning algorithms.