دانلود رایگان مقاله انگلیسی اثر همزمانی نانوفیلرهای نقره اکسید گرافین بر عملکرد مهندسی غشاهای نانوسیم پیچیده پلی الکترولیت - وایلی 2018

ABSTRACT:

The poor mechanical and antibacterial performance has become a big hurdle for extending the application of polyelectrolyte complex (PEC) nanofibers in various fields. In this study, chitosan/gelatin (CG) composite nanofiber system was used for portraying the synergistic enhancement of mechanical and antibacterial properties of PEC nanofiber membranes by inclusion of graphene oxide-silver (GO-Ag) nanofillers. In particular, the introduction of 1.5 wt % GO-Ag has raised the elastic modulus and tensile strength of CG nanofiber membrane by 105% and 488%, respectively, which are partially attributed to the alleviated restacking of graphene sheets by the anchored AgNPs. Meanwhile, the diameters of inhibition zone against Escherichia coli and Staphylococcus aureus on LB-agar plates induced by GO-Ag/CG nanofiber membranes are increased by 80.5% and 50.1%, respectively, compared to that by CG membrane. The synergistic improvement of antimicrobial performance of GO-Ag/CG may be related to the accumulation of microorganisms induced by GO. In summary, the incorporation of GO-Ag composite nanofillers has emerged as an effective strategy for engineering PEC nanofiber membranes for potential applications in nanomedicine and tissue engineering.

CONCLUSIONS

In this work, the potential improvement in the mechanical and antibacterial properties of CG nanofiber membranes with the incorporation of GO-Ag composite fillers was thoroughly exploited. First of all, the successful synthesis of GO-Ag by in situ reduction of Ag1 on the surface of GO sheets was confirmed by TEM, UV–vis, XRD, EDS, and FTIR analysis. The incorporation of GO-Ag nanocomposites can synergistically enhance both mechanical and antibacterial properties of CG composites matrix. The introduction of GO-Ag induces 105% enhancement of the elastic modulus and 488% augment of tensile strength on CG nanofiber membranes. The synergistically enhancement in the mechanical properties on of GO-Ag/CG are partially resulted from the alleviated restacking of graphene sheets by the anchored AgNPs, which is supported by TEM and DSC results. Meanwhile, owing to excellent antibacterial ability of GO-Ag, the diameters of inhibition zone of GO-Ag/CG nanofiber membranes against E. coli and S. aureus are enlarged by 80.5% and 50.1% on top of that of CG, respectively. The synergistical improvement on antibacterial ability of GO-Ag/CG may involve the accumulation of microorganisms to the vicinity of AgNPs by GO. The incorporation of GO-Ag possesses great potential for simultaneously improving mechanical and antibacterial performance of PEC nanofibers in biomedical applications.