Improving the properties of fish skin collagen/silk fibroin dressing by chemical treatment for corneal wound healing

Natural biomaterials are crucial in ocular tissue engineering because they allow cells to proliferate, differentiate, and stratify while maintaining the typical epithelial phenotype. In this study, membranes as dressings were formed from silk fibroin and collagen (Co) extracted from fish skin and then modified with carbodiimide chemical cross linker in different concentrations. The samples were evaluated by different analyses such as structural, physical (optical, swelling, denaturation temperature, degradation), mechanical, and biological (viability, cell adhesion, immunocytochemistry) assays. The results showed that all membranes have excellent transparency, especially with higher silk fibroin content. Increasing the cross linker concentration and the ratio of silk fibroin to Co increased the denaturation temperature and mechanical strength and, conversely, reduced the degradation rate and cell adhesion. The samples did not show a significant difference in toxicity with increasing cross linker and silk fibroin ratio. In general, samples with a low silk fibroin ratio combined with cross linker can provide desirable properties as a membrane for corneal wound healing.