Inulin-based hydrogel e-skin for human-machine interaction

Electronic skin is a flexible, stretchable smart material widely used in fields such as healthcare, robotics, and smart wearables. However, electronic skin still faces multiple challenges in sensitivity, conductivity, biocompatibility, and data processing. In this study, we report a multifunctional hydrogel, named PIPC, prepared by semi-interpenetrating networks of acrylamide and inulin, combined with ionic interactions. The PIPC hydrogel exhibits adhesion, conductivity (≈5.2 S/m), high fracture strength (≈60 kPa), and stretchability (with a maximum strain of up to 1552 %). Notably, its gauge factor (GF) reaches 5.54, demonstrating exceptional strain sensitivity. The introduction of inulin significantly enhances the biocompatibility of the PIPC hydrogel, making it more suitable for contact with the human body. Using PIPC e-skin, we have successfully realized human-machine interaction systems such as real-time control of mechanical hand, game interaction, and emergency signal sending. This study highlights the tremendous potential of PIPC hydrogel e-skin in biomedical monitoring, smart sensing, and human-machine interaction technologies.