Research progress of natural polysaccharide-based and natural protein-based hydrogels for bacteria-infected wound healing

Healing of infected wounds has always been a challenge in clinical care. There is an urgent need to develop an effective and economical wound dressing combining antimicrobial activity and healing-promoting properties. Hydrogels have received increasing attention among the various available dressings due to their adjustable physicochemical properties and three-dimensional cross-linked polymer networks that can absorb and retain large amounts of water. Depending on the origin of the main components of the hydrogel network, they can be classified as natural or synthetic hydrogels. Hydrogels made from natural polymers are popular for their excellent biocompatibility, low toxicity, and functionality. Various strategies have been developed to enhance the performance of wound dressings further to endow the hydrogels with excellent antibacterial activities. This review described natural polysaccharide-based and natural protein-based hydrogels including chitosan (CS), hyaluronic acid (HA), sodium alginate (SA), gelatin, etc., and their derivatives, which were used to address the limitations of conventional hydrogel dressings by adding other antimicrobial ingredients, thereby effectively resisting bacterial infections and promoting wound healing. The application of natural macromolecular composite hydrogels combined with phototherapy in the treatment of drug-resistant bacterial infections was also reviewed, providing a reference for applying natural polymer-based hydrogels as wound dressings with antimicrobial properties to achieve effective wound healing.