An Antifouling and Antimicrobial Zwitterionic Nanocomposite Hydrogel Dressing for Enhanced Wound Healing

Antibacterial hydrogels have received intensive interest in soft tissue repair, especially for preventing infections associated with impaired wound healing. However, developing an inherent antibacterial hydrogel dressing with antifouling ability without causing secondary damage to repaired tissues has proven to be promising and challenging. In this work, a mussel-inspired zwitterionic sulfobetaine acrylamide hydrogel incorporated with laponite (LAP) nanoplatelets and methacrylamide dopamine (DMA) has been developed for effective wound dressings, where LAP nanoplatelets and DMA endow the hydrogel with enhanced mechanical strength and substance adhesiveness, respectively. Moreover, LAP nanoplatelets could immobilize hydrophobic curcumin to form complexes, realizing the controlled release of curcumin to provide antimicrobial activities. In vitro results showed that hydrogels did not cause obvious cytotoxicity and hemolysis, but they still can well resist bovine serum albumin (BSA) adsorption. Wound closure and histopathological experiments have been performed in vivo to evaluate the therapeutic effects of the hydrogel by a full-thickness skin defect mouse model, and the results demonstrated that infected wounds could be well closed after being treated with the hydrogel for 15 days. Meanwhile, the full re-epithelialization and total formation of new connective tissues can be clearly observed by histological analysis. Moreover, the hydrogel could be easily removed from recovered tissues without causing secondary damage. Therefore, this antifouling and antimicrobial hydrogel dressing with suitable adhesiveness would provide a new strategy for wound healing without causing secondary damage.