Polyvinyl Alcohol/Silk Fibroin/Borax Hydrogel Ionotronics: A Highly Stretchable, Self-Healable, and Biocompatible Sensing Platform.

Abstract

The emergence of hydrogel ionotronics has significantly extended the applications of soft electronics by allowing intimate interfaces between electronic components and biological/engineered surfaces for improved sensing and communication with surrounding stimuli. However, hydrogel ionotronic devices that combine high stretchability, self-healing, good water-retention and biocompatibility are still needed. Here, we report a biocompatible ionic hydrogel prepared from polyvinyl alcohol, silk fibroin, and borax. In this ionic hydrogel, polyvinyl alcohol and borax offer high stretchability and conductivity, respectively, while silk fibroin improves the stability of the hydrogel and increases water uptake by the gels. The hydrogels feature strains larger than 5,000%, good water retention, self-healing and tunable conductivity and adhesive capabilities. We also demonstrate the utility of the hydrogel as a sensing platform to monitor human body motion for applications in health management, soft robotics, and human-machine interfaces.