No abstract

Biomolecule incorporated PCL nanofibrous scaffolds supporting meniscal cell attachment and proliferation.

Poly e-caprolactone (PCL)-based nanocomposite films were prepared by solvent casting method with different electrically conducting carbon nanofillers like carbon nanofiber (CNF), nanographite and liquid exfoliated graphite. These nanocomposite films show remarkable increase in both surface and bulk electrical conductivity. Continuous network of nanofillers in polymer matrix was observed under high-resolution transmission electron microscopy (HRTEM). The spreading resistance images in AFM showed the presence of nanofillers on the nanocomposite films. These films reveal strong directional effect in electrical conductivity towards longitudinal direction than transverse. PCL film dispersed with 10 % (w/w) CNF showed an electrical conductivity of 19 S/m at longitudinal direction as compared to 1 S/m at transverse direction. This can be best explained with the arrangement of nanofillers along longitudinal direction during solution casting method which is evident from HRTEM images. The electrical conductivity of the nanocomposite films increased in the presence of phosphate buffer saline and simulated body fluid with time. MTT and nuclear staining experiments with osteoblast MG63 cells clearly demonstrated good biocompatibility of these materials. Among all the nanofillers, CNF looks most promising for biomedical applications of PCL-based conducting nanocomposites, as it shows high electrical conductivity and good cell proliferation.

In this study, silk fibroin nanofibrous scaffolds were developed to investigate the attachment and proliferation of primary human meniscal cells. Silk fibroin (SF)-polyvinyl alcohol (PVA) blended electrospun nanofibrous scaffolds with different blend ratios (2:1, 3:1, and 4:1) were prepared. Morphology of the scaffolds was characterized using atomic force microscopy (AFM). The hybrid nanofibrous mats were crosslinked using 25 % (v/v) glutaraldehyde vapor. In degradation study, the crosslinked nanofiber showed slow degradation of 20 % on weight after 35 days of incubation in simulated body fluid (SBF). The scaffolds were characterized with suitable techniques for its functional groups, porosity, and swelling ratio. Among the nanofibers, 3:1 SF:PVA blend showed uniform morphology and fiber diameter. The blended scaffolds had fluid uptake and swelling ratio of 80 % and 458 ± 21 %, respectively. Primary meniscal cells isolated from surgical debris after meniscectomy were subcultured and seeded onto these hybrid nanofibrous scaffolds. Meniscal cell attachment studies confirmed that 3:1 SF:PVA nanofibrous scaffolds supported better cell attachment and growth. The DNA and collagen content increased significantly with 3:1 SF:PVA. These results clearly indicate that a blend of SF:PVA at 3:1 ratio is suitable for meniscus cell proliferation when compared to pure SF-PVA nanofibers.