Silver Nanoparticles Modified Electrospun Nanofibers:Preparation And Applications

Electrospinning technology is an efficient method to prepare nanofibers. This dissertation contains the following two parts about composite nanofibers based on electrospinning.Electros pun PET nanofibers and the antibacterial application of functionalized PET/PDA-Ag NPs composite nanofibers.Polyethylene terephthalate (PET) nanofibers and PET/PDA-AgNPs composite nanomaterial were prepared based on the electrospinning technology. PET was dissolved with the mixture of trifluoroacetic acid (TFA) and dichloromethane (DCM) (2:1), concentration of 30%(w/v). PET/PDA was obtained through mussel-inspired chemistry of dopamine on the surface of PET nanofibers. Silver nanoparticles were synthesized with reduction effect of PDA. The nano-morphology of PET, PET/PDA, PET/PDA-AgNPs were characterized by scanning electron microscopy (SEM). The existence of AgNPs was proved by X-ray photoelectron spectroscopy (XPS). The antibacterial activities of PET/PDA-AgNPs against Gram positive, S. aureus, and Gram negative, E. coli. were tested though inhibition zone and antibacterial coefficient, which confirmed PET/PDA-AgNPs composite nanomaterial had the antibacterial activity.Preparation of PCL@CTS coaxial nanofibers and antibiosis research after functionalized silver nanoparticlesIn this work, we prepared Polycaprolactone@Chitosan shell-core coaxial nanofibers based on coaxial electrospinning technology then characteristiced with silver nanoparticles for antibacterial application. PCL nanofibers were obtained by electrospinning with mixture of chloroform and methanol(3:1).8% of PCL solution(w/v) was put in inner syringe as core material and 2% of CTS solution (w/v) was put in outer syringe as shell material. PCL nanofibers and PCL@CTS were characterized by SEM, TEM, Fourier transform infrared spectroscopy (FTIR); contact angle (CA) was checked, PCL@CTS has higher hydrophilicity than PCL. MTT test was taken to evaluate the cellular biocompatibility of nanofibers. Silver nanoparticles (AgNPs) were synthesized and immobilized on the coaxial nanofibers. Gram negative, E.coli, and Gram positive, S.aureus, were tested against modified coaxial nanofibers for antibacterial activity,13 mm inhibition zone was measured against E. coli which was higher than S. aereus.