الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
The current study was conducted to develop a series of nanofiber scaffolds for guided tissue regeneration (GTR) and guided bone regeneration (GBR) prepared by electrospinning. The nanofibers are based on polycaprolactone (PCL) or a mixture of polylactic acid and cellulose acetate (PLA/CA). Additionally, different concentrations of hydroxyapatite nanoparticles (HANPs) and silver nanoparticles (AgNPs) were added to the scaffold to enhance their bone regeneration and antibacterial activity. Hydroxyapatite nanoparticles (HANPs) were prepared using chemical precipitation method. The chemical composition and microstructure of the prepared hydroxyapatite were characterized by X-ray diffraction (XRD) analysis, Fourier Transform Infra-Red (FT-IR) Spectroscopy and transmission electron microscopy (TEM). Silver nanoparticles (AgNPs) were prepared using Callistemon viminalis extract. AgNPs synthesis was monitored using UV-Vis spectrometry, FTIR, X-ray diffraction and TEM . The synthesized nanofibers were evaluated using scanning electron microscopy (SEM), FTIR and Differential Scanning Calorimetry (DSC). Then, tensile strength, biodegradation and bioactivity of nanofibers were evaluated. Additionally, silver release, antibacterial activity and cytotoxicity of nanofibers were assessed. The SEM images of nanofibers showed interconnected randomly organized fibers. The tensile properties of nanofibers improved by the addition of 10% hydroxyapatite nanoparticles but deteriorated by increasing the concentration to 20%. It was found that addition of HANPs enhances deposition of CaP on nanofibers especially with the nanofibers containing 20wt % HANPs. In addition, nanofibers showed degradation about 30–40% losing of the weight in 8 weeks for the PCL nanofibers and around 40–70% for the PLA/CA nanofibers. The nanofibers provided significant improvement in the antibacterial activity. Results of In-vitro studies showed that the addition of hydroxyapatite nanoparticles resulted in improved cell viability by around 50% for both types of fibers.