Stretchable and Heat-Resistant Protein-Based Electronic Skin for Human Thermoregulation

Silk protein is one of the a promising materials for on-skin and implantable electronic devices due to its biodegradability and biocompatibility. However, its intrinsic brittleness as well as poor thermal stability limits its applications. In this work, robust and heat-resistant silk fibroin composite membranes (SFCMs) are synthesized by mesoscopic doping of regenerated silk fibroin (SF) via the strong interactions between SF and polyurethane. Surprisingly, the obtained SFCMs can endure the tensile test (>200%) and thermal treatment (up to 160 degrees C). Attributed to these advantages, traditional micromachining techniques, such as inkjet printing, can be carried out to print flexible circuits on such protein substrate. Based on this, Ag nanofibers (NFs) and Pt NFs networks are successfully constructed on both sides of the SFCMs to function as heaters and temperature sensors, respectively. Furthermore, the integrated protein-based electronic skin (PBES) exhibits high thermal stability and temperature sensitivity (0.205% degrees C-1). Heating and temperature distribution detection are realized by array-type PBES, contributing to potential applications in dredging of the blood vessel for alleviating arthritis. This PBES is also inflammation-free and air-permeable so that it can directly be laminated onto human skin for long-term thermal management.