Biophysical properties of electrospun chitosan-grafted poly(lactic acid) nanofibrous scaffolds loaded with chondroitin sulfate and silver nanoparticles.

The aim of this work was to study the biophysical properties of the chitosan-grafted poly(lactic acid) (CH-g-PLA) nanofibers loaded with silver nanoparticles (AgNPs) and chondroitin-4-sulfate (CS). The electrospun CH-g-PLA:AgNP:CS nanofibers were manufactured using the electrospinning technique. The microstructure of the CH-g-PLA:AgNP:CS nanofibers was investigated by proton nuclear magnetic resonance (H-NMR), scanning electron microscopy (SEM), UV-Visible spectroscopy (UV-Vis), X-ray diffraction (XRD), and Fourier transform infrared (ATR-FTIR) spectroscopy. ATR-FTIR and H-NMR confirm the CH grafting successfully by PLA with a substitution degree of 33.4%. The SEM measurement results indicated apparently smooth nanofibers having a diameter range of 340 ± 18 nm with porosity of 89 ± 3.08% and an average pore area of 0.27 μm. UV-Vis and XRD suggest that silver nanoparticles with the size distribution of 30 nm were successfully incorporated into the electrospun nanofibers. The water contact angle of 12.8 ± 2.7° reveals the hydrophilic nature of the CH-g-PLA:AgNP:CS nanofibers has been improved by CS. The electrospun CH-g-PLA:AgNP:CS nanofibers are found to release ions Ag+ at a concentration level capable of rendering an antimicrobial efficacy. Gram-positive bacteria () were more sensitive to CH-g-PLA:AgNP:CS than Gram-negative bacteria (). The electrospun CH-g-PLA:AgNP:CS nanofibers exhibited no cytotoxicity to the L-929 fibroblast cells, suggesting cytocompatibility. Fluorescence microscopy demonstrated that CS promotes the adhesion and proliferation of fibroblast cells onto electrospun CH-g-PLA:AgNP:CS nanofibers.