Electrospinning Nano-copper/polymer Composite Fibers And Antibacterial Activity

The preparation of biodegradable polymer nanofibers by electrospinning has the advantages of large specific surface area,high porosity,and controllable fiber diameter.It can be widely used in biomedical fields such as wound dressings,drug delivery systems,and skin care.It has become a hotspot in the research of electrospinning materials,but there are few studies on its antibacterial functionality.Therefore,in this paper,poly(?-caprolactone)(PCL)and gelatin(Gt)are used as the matrix,and copper nanoparticles are the antibacterial active components.Two types of new antibacterial composite fiber materials,Cu/PCL and Cu/PCL/Gt,were prepared by electrospinning,and their composition,structure and antibacterial activity were characterized.The main research contents are as follows:(1)Using chitosan as a protective agent and ascorbic acid as a reducing agent,copper nanoparticles(CuNPs)were synthesized by microwave heating,and their composition,structure and morphology were characterized.The results of the study indicate that CuNPs were successfully synthesized and their particle size was concentrated at 5-11 nm.(2)Cu/PCL nanofiber membranes were prepared by electrospinning of PCL spinning solutions with different amounts of CuNPs.The composition,structure and morphology were characterized by SEM,FT-IR,TG and ICP,and their Contact angle,mechanical properties and antibacterial activity were studied.The results showed that when the mixed solvent DCM/DMF =1:9,the PCL polymer concentration was 8 wt.%,and the amount of CuNPs added was 0.4 wt.%,the prepared Cu/PCL nanofiber membrane had uniform morphology,good mechanical properties,and with good antibacterial activity.(3)Cu/PCL/Gt composite nanofiber membranes were prepared by electrospinning with different amounts of CuNPs in PCL and Gt mixed spinning solutions,and their composition,structure,morphology and properties were characterized.Through research,it was found that when PCL/Gt(w/w)is 5:5 and the mixed solvent ratio AA/FA is 7:3,fibers with uniform morphology can be obtainedwith good hydrophilicity and high porosity.The 0.5 wt.% sample had good antibacterial activity against E.coli and S.aureus.