A Multifunctional Antibacterial Hydrogel with Injectable, Antifouling, and Conductive Properties

Zwitterionic hydrogels have shown promise as effectiveantifoulingmaterials in wound dressing applications owing to their robust hydratelayer that offers protection against microbial infections. However,the traditional covalently crosslinked zwitterionic hydrogels maynot be sufficient to adapt to irregular injury sites and fully addressmicrobial infections within the wound. Herein, we propose an injectablezwitterionic hydrogel that utilizes dynamic hydrazone chemistry viaaldehyde and hydrazide functional groups and contains N-halamine antibacterial agents. The dual dynamic exchangeable covalentlyand physically crosslinked structure resulting from the combinationof hydrazone bonds and zwitterion interactions facilitates instantaneousgelation (within a few seconds) and extreme stability without anydegradation (for over 2 months). The hydrogels exhibit remarkablefouling resistance against proteins and bacteria while demonstratingexcellent antibacterial performance in vitro without compromisingcytocompatibility. More importantly, we demonstrate their inherentconductivity properties and sensitivity to external pressure. Thecombination of the injectability, antifouling, antibacterial, cytocompatibility,and electrical conductivity properties achieved offers the potentialto expand the utility of zwitterionic hydrogels in biological applications.