Improved biological activities of dual nanofibrous chitosan/bacterial cellulose wound dressing by a novel silver-based metal-organic framework

The worldwide menace of antibiotic-resistance bacteria could be weakened by development and utilization of impressive and multi-functional bactericidal materials. In this work, a novel silver-based metal-organic framework (SOF) was synthesized via a facile and environmentally-friendly process. Different amounts of the SOF nanoparticles incorporated in dual nanosized chitosan/bacterial cellulose (CS/BC) fibrous composites to make a hybrid antibacterial porous structure for mimicing the skin extracellular matrix. X-ray diffraction revealed the successful synthesis of the SOF and CS/BC-SOF nanocomposites using green solvents at ambient temperature. Energy-dispersive X-ray spectroscopy confirmed the presence of Ag species in the SOF structures. Electron microscopy images showed ∼30 nm nanofibers of the CS/BC blend embedded with uniform distribution of the SOF nanoparticles. MTT assay demonstrated the best biocompatibility performance with cell viability of ∼94% for the CS/BC-25%SOF nanocomposite. Antibacterial tests indicated adequate and efficient antibacterial activity of all SOF-containing samples against E. coli and S. aureus strains. Animal in vivo studies demonstrated excellent healing with ∼74% wound closure for the wounds treated using CS/BC-25%SOF nanocomposite during the 2nd week after surgery. Hematoxylin and eosin staining revealed successful healing and tissue regeneration for the wounds treated using CS/BC-25%SOF nanocomposite. The results suggest that the new produced nanocomposites, especially the CS/BC-25%SOF, can potentially be used as excellent platforms for wound dressing. Schematic for biocompatibility and antibacterial mechanisms of the nanoscale fibrous CS/BC-SOF composite as a new biomaterial for wound healing application. [Display omitted]