Advances in the Construction and Application of Lignin-Based Hydrogels

Lignin, the most abundant natural aromatic polymer globally, has garnered considerable interest due to its rich and diverse active functional groups and its antioxidant, antimicrobial, and adhesive properties. Recent research has significantly improved the performance of lignin-based hydrogels, suggesting their substantial potential in fields such as biomedicine, environmental science, and agriculture. This paper reviews the process of lignin extraction, systematically introduces synthesis strategies for preparing lignin-based hydrogels, and discusses the current state of research on these hydrogels in biomedical and environmental protection fields. It concludes by identifying the existing challenges in lignin hydrogel research and envisioning future prospects and development trends.