Study on Preparation and Performance of Arg-Glu-Asp-Val Modified Silk Fibroin Tube

Purpose: To prepare a silk fibroin scaffold with grooved structure modified by REDV polypeptide. Method: A silk fibroin film was prepared on a PDMS film containing a 30-micron groove structure and rolled into a tube. The REDV polypeptide is covalently attached to the surface of the silk fibroin graft for modification by dopamine modification. Scanning electron microscope was used to observe the micro morphology of the inner surface, and the electronic universal test (TFW-58) machine was used to detect the changes in the mechanical properties of the silk fibroin scaffold modified with REDV polypeptide. RSC96 cells were planted on the inner surface of the silk fibroin scaffold for 1 3 days, and the influence of the groove structure on the inner surface of the silk fibroin scaffold on cell growth was observed. CCK-8 (cell counting Kit-8) assay was used to detect the proliferation of RSC96 cells on the surface of silk fibroin grafts. SD rats were used to prepare sciatic nerve injury models. Silk fibroin catheters (SF), grooved silk fibroin catheters (TOPOLOGY), REDV polypeptide modified silk fibroin catheters (REDV), REDV modified silk fibroin catheters with grooved structure (TOPOLOGY/REDV) were used to perform bridge repair. 12 weeks after the operation, the target muscle wet weight ratio and the longitudinal section of the transplanted sciatic nerve were measured by immunofluorescence staining. Results: Scanning electron microscopy showed that both the TOPOLOGY group and the TOPOLOGY/REDV group had a uniform groove structure; the mechanical test results showed that the mechanical properties of the silk fibroin scaffold modified with REDV polypeptides had been improved; RSC96 cells and silk fibroin grafts were co-cultured, and it was found that the groove structure on the surface of the grafts had a guiding effect on the growth of cells; CCK-8 cell viability test showed that the silk fibroin scaffold modified by REDV polypeptide is more biological than simple silk fibroin scaffold. The CCK-8 cell viability test showed that the silk fibroin scaffold modified by REDV polypeptide has improved biocompatibility compared with the pure silk fibroin scaffold; the target muscle restored wet weight ratio and sciatic nerve longitudinal section immunofluorescence staining results 12 weeks after operation, which shows that the silk fibroin scaffold modifies with REDV polypeptide and has a grooved structure that can promote the adhesion and growth of cells and the repair of damaged nerves. Conclusion: REDV polypeptide modified silk fibroin scaffold with groove structure has good biocompatibility, promotes cell adhesion and growth tendency, and provides a new application for silk fibroin in the field of nerve injury and regeneration.