Research progress on conductive hydrogels derived from natural biopolymers as emerging interface materials for motion detection wearable sensors

The rapid advancement of flexible electronic devices is contingent upon the support of high-performance conductive materials. In recent years, conductive hydrogels (CHs) have garnered significant attention in the wearable sensor domain attributed to their exceptional flexibility, versatility, and biocompatibility. Among the diverse polymer materials employed in CH manufacturing, natural biopolymers excel due to their biocompatibility, degradability, ecological soundness, and economical viability. This paper comprehensively synopsizes research advancements in wearable sensor applications utilizing natural biopolymer-derived CHs. The paper commences by investigating the pivotal functional attributes of CHs, including conductivity, mechanical properties, environmental adaptability, biocompatibility, and adhesive properties. Furthermore, the paper delves into the significant role of several typical natural biopolymers (polysaccharides and proteins) in enhancing CH performance and elaborates on material optimization strategies for designing high-performance, multifunctional wearable sensors. Additionally, the paper synthesizes the primary challenges encountered in contemporary research and market development. Ultimately, the paper proposes novel directions and unveils new developmental opportunities for natural biopolymer-based wearable sensors.