3D-printable liquid metal-based hydrogel for use as a multifunctional epidermal sensor

). The Ca-PAA-LM conductive hydrogel prepared in this way combined the multifunctional properties of plasticity, stretchability, printability, self-healing, and multiple sensing capabilities. Therefore, the epidermal sensor based on this hydrogel showed stable monitoring of human health conditions, including all-around body movements and electrophysiological signals, such as electrocardiography and electromyography. The conductive hydrogel developed in this study provides an ideal material choice for personalized health monitoring devices and also provides a path for the development of a new generation of multifunctional flexible sensors.