Polysaccharide-based hydrogels: Materials, preparation, and applications in medicine, food, adsorption, and agriculture

Hydrogels have attracted extensive attention due to their good biocompatibility, stimulus responsiveness, and tunable mechanical properties. Among many natural polymeric materials, polysaccharides are widely regarded as ideal candidates for the preparation of functional hydrogels because of their good biocompatibility, degradability, and high gel strength properties. Unfortunately, the research on the composition and properties optimization of polysaccharide-based hydrogels (PBHs) is still in their infancy, which limits the wide application of PBHs. Hence, it is important to explore the raw material selection and synthesis process of PBHs in depth. This review systematically summarizes the sources (chitosan, alginate, xanthan gum, konjac glucomannan, pectin, κ-carrageenan, cellulose, hyaluronic acid, starch, glucan, etc.) and type (polysaccharide/polysaccharide, polysaccharide/protein, polysaccharide/organic acid, and polysaccharide/nanomaterial composite hydrogels) of PBHs, which provides new research directions for solving the shortcomings of single PBHs in stability and load capacity. Moreover, this review systematically outlines the progress of PBHs in biomedicine, food industry, adsorption, and agriculture, as well as also discusses the challenges faced in their practical applications and future perspectives. For instance, the integration of interdisciplinary technologies (3D printing, artificial intelligence, etc.) can enhance the gel strength and thermal stability of PBHs, thereby improving their application in biomedicine. The findings provide important references for the further development and application of PBHs. • The materials of polysaccharide-based hydrogels (PBHs) were reviewed. • Physical/chemical/dual network cross-linking methods can effectively prepare PBHs. • PBHs are used in the fields of biomedicine, food industry, adsorption, agriculture, etc.