静电纺PVA-SbQ/SF/Ag-ZIF复合纤维膜的性能分析OA

Chronic non-healing wounds demand advanced wound dressings with optimized mechanical robustness,high biocompatibility,and sustained antibacterial efficacy.To overcome the limitations of conventional silver-based dressings—particularly the burst release of Ag+ions leading to cytotoxicity and short functional duration—a novel"dual barrier"strategy is proposed through rational material design and structural engineering.In this work,a multifunctional electrospun nanofibrous membrane is developed by integrating silk fibroin(SF)as a biocompatible and mechanically resilient matrix with photosensitive polyvinyl alcohol-styrylpyridinium salt(PVA-SbQ)to enhance flexibility and water stability.To achieve controlled Ag+release,zeolitic imidazolate framework-8(ZIF-8)with well-defined micropores is employed as a nanoreservoir,pre-loaded with Ag+to form Ag-ZIF nanoparticles.These components are subsequently fabricated into a PVA-SbQ/SF/Ag-ZIF composite nanofiber membrane via electrospinning. The effect of Ag-ZIF loading(0-10%)on the morphological,structural,thermal,and mechanical properties of the composite is systematically evaluated.Scanning electron microscopy(SEM)reveals the formation of uniform,bead-free nanofibers with homogeneous dispersion of Ag-ZIF nanoparticles at loadings up to 5%,without significant aggregation.X-ray diffraction(XRD)and Fourier-transform infrared spectroscopy(FTIR)confirm the successful incorporation of Ag-ZIF into the SF matrix and the development of β-sheet secondary structures in SF,indicating strong interfacial compatibility.Thermogravimetric analysis(TGA)demonstrates enhanced thermal stability,with an increased initial decomposition temperature upon Ag-ZIF incorporation.Mechanical testing shows a balanced strength-ductility profile,achieving a maximum tensile strength of 11.85±0.57 MPa and an elongation at break of 92.39%±3.03%at 2.5%Ag-ZIF loading.Contact angle measurements indicate a tunable surface hydrophobicity with increasing Ag-ZIF content. Notably,the composite membrane exhibits excellent and prolonged antibacterial activity against Escherichia coli and Staphylococcus aureus.The sustained Ag+release is attributed to the synergistic"dual barrier"mechanism:confinement within ZIF-8 micropores and physical encapsulation by the electrospun fiber matrix.At 5%Ag-ZIF loading,bactericidal efficacy reaches 99.80%and 99.56%,respectively,with pronounced inhibition zones(14.10 mm and 14.43 mm),outperforming conventional silver-loaded materials at equivalent Ag content.This study presents a promising platform for next-generation wound dressings by engineering a biomimetic,mechanically adaptive,and sustained-release antibacterial nanofibrous system through scalable electrospinning technology.