Macroheterocycle-functionalized PVDF meshes with hybrid nanocomposite coatings for antibacterial wound care

We herein report the preparation of a novel wound healing material by functionalizing polyvinylidene fluoride (PVDF) meshes with a hybrid nanocomposite system consisting of a 40-membered macroheterocycle (MHC), Dashsalahli bentonite nanoparticles (BN), silver nanoparticles (AgNP), and propolis (P), which were chosen according to their complementary roles: MHC serves as an antibacterial scaffold, BN serve as a stabilizer and release controller agent, AgNP serve as a potent bactericidal agent and P serves as a natural bioactive product. The functionalization and stability of the designed novel hybrid nanocomposite systems were evaluated using SEM, EDAX, TEM, and zeta potential analysis. Antibacterial activity was evaluated against various strains of S. aureus using MIC, agar diffusion and time-kill kinetic assays, which revealed a potent bactericidal effect within 8 hours of treatment with the MHC@BN@AgNP nanocomposite in the case of S. aureus ATCC 6538, with an MIC value of 0.25 µg mL^-1. TEM analysis revealed that the sample caused bacterial cell wall disruption and intracellular degradation. In addition, hemolysis assays showed low hemolytic activity for most hybrid nanocomposites, and ex vivo porcine skin decontamination assays revealed an effective reduction in S. aureus 1199B strain colonization under relevant biological conditions. The obtained results suggest that the designed nanocomposite coated with PVDF meshes is a potential candidate for advanced wound care applications targeting S. aureus infections.