Advances in plant polysaccharide-based self-healing hydrogels.

Traditional hydrogels suffer from irreversible structural damage under mechanical stress, which shortens service lifetimes and restricts their practical deployment in dynamic scenarios. Self-healing hydrogels constructed from plant-derived polysaccharides stand out against synthetic polymers and other biopolymers as promising biomaterials, owing to their abundant terrestrial resources, favorable biocompatibility, and inherent biodegradability. This review systematically summarizes recent advances in self-healing hydrogels based on major plant polysaccharides, including cellulose, hemicellulose, starch, galactomannans and their derivatives. The review explores the molecular design principles and intrinsic self-healing mechanisms of these polysaccharide systems, and compares how chemical structures of different plant polysaccharides impact healing efficiency and mechanical properties. The merits and demerits of each polysaccharide type are discussed with respect to solubility, mechanical robustness, gelation characteristics, and long-term stability. Additionally, the review identifies key challenges currently confronting the field, including the intrinsic trade-off between self-healing efficiency and mechanical strength, inadequate long-term stability under complex physiological conditions, cumbersome modification procedures, and limited scalability for large-scale production. Future research endeavors should prioritize the modification of polysaccharide molecular structures, innovative cross-linked network construction, and computational modeling to predict structure-property relationships, thereby facilitating the application of plant polysaccharide in high value-added fields.