Designing and Construction of Silk, Polyvinyl Alcohol, Gelatin Nano-Scaffold for Using in Articular Cartilage Tissue Engineering Download PDF

The cartilage is a type of connective tissue, supporting the soft tissues due to strength of its extracellular matrix, which allows this tissue tolerate the mechanical pressures without permanent deformation. Due to its smooth elastic surface, it gives slippery and impact property. In this research, combined silk fibroin-gelatin -polyvinyl alcohol scaffolds were developed and studied for cartilage tissue engineering. Silicon fibroin silk and gelatin are used as a bed for cell adhesion and proliferation. In this research, the nanofibrous silk fibroin-gelatin- poly-vinyl alcohol scaffolds were prepared using electrospinning method. First, silk fibroin-gelatin solution with a ratio of 70 to 30% and a separate 8% poly-vinyl alcohol solution were prepared, and then, nano-fibers were constructed through two nozzles by using electrospinning method. Then, imaging was performed using scanning electron microscopy, infrared spectroscopy, biodegradation tests and tensile strength test. After qualitative confirmation of nano-fibers, cell culture of cartilage cells was performed on the scaffold for 30 days. Then, imaging by scanning electron microscopy, hematoxylin-eosin staining, and measurement of glycosylation of amino glycan were performed. The silk fibroin / gelatin / poly-vinyl alcohol scaffold supports the cell growth and chondrogenic phenotypes, indicating a relative expression of type II against collagen Type I. Cartilage cells have grown on the scaffold and synthesized glycosaminoglycan. The results of examining the scaffold revealed that the mean diameter of the fiber was 155.75 nm and the biodegradability was 7% after three weeks. In the examinations related to FTIR silica fibroin, we had three peaks of functional groups related to silk fibroin, so the presence of silk fibroin in the silk fibroin scaffold is confirmed. In examinations related to FTIR gelatin, we have three peaks related to the gelatin functional group, so the presence of gelatin in the silk fibroin scaffold is confirmed, and the presence of the OH group confirms the presence of poly vinyl alcohol. In the studying the cell growth by hematoxin-eosin staining, it is shown that at the end of the third week, 20 cells (counting at 200 micrometers) have been grown. The results indicate that silk fibroin-gelatin-poly vinyl alcohol scaffolds might be an appropriate alternative to artificial cell scaffolds for cartilage tissue engineering.