In situ cross-linked polysaccharide hydrogel as extracellular matrix mimics for antibiotics delivery

• We use chitosan and dextran which is natural polysaccharides as the materials of hydrogel.
• We use the hydrogel for wound healing, and it has better antibacterial properties than other wound dressings.
• The hydrogel are synthesized in 37 °C easily and show good swelling properties and regular porous structure.

Many synthetic hydrogels for drug delivery have been based on polyethylene glycol which is non-natural, non-biodegradable and only terminal-functionalizable. The polysaccharides dextran and chitosan not only are highly hydrophilic, biodegradable and pendant-functionalizable, but also more closely mimic the nature extracellular matrix glycosaminoglycans. Here, a biomimetic hydrogel based on chitosan and dextran was synthesized by the Michael addition reaction. The hydrogels have good swelling and cytocompatibility against NIH3T3. Moreover, vancomycin-loaded hydrogels were formed in situ, and could kill both Gram-positive bacteria and Gram-negative bacteria, indicating that the hydrogel as a wound dressing could provide protection against bacterial infection. Notably, the drug release was controlled via modifying the compositions. Therefore, the biomimetic polysaccharide hydrogels as a promising carrier have potential application for wound healing.