Preparation And Properties Of Modified Silk Fibroin/calcium Silicate/chitosan Bone Tissue Engineering Scaffolds

Objective:Bone defects caused by maxillofacial trauma,tumor,congenital malformation and other diseases are very common in the field of oral and maxillofacial surgery.Bone defects seriously affect the shape and function of maxillofacial region,and cause inconvenience to the life of patients.Bone tissue engineering can effectively restore bone defects without taking bone from the body or allograft or xenograft bone.Using the principle of tissue engineering,we prepared fibroin protein/calcium silicate/chitosan composite bone tissue engineering scaffold,modified the surface to improve its osteogenic performance,and tested the physical and biological properties of the scaffold.So we can use the modified scaffold to treat bone defect.Methods:Biodegradable silk fibroin protein was extracted from natural silk by degumming and dialysis.By means of freeze-drying technology,the silk fibroin,chitosan,calcium silicate and other materials were mixed evenly,to prepare the scaffold.Dopamine was used to modify the surface of the tissue engineering scaffold to obtain the adhesion and load performance and improve the biological activity of the material surface.The surface morphology of the scaffold was observed by scanning electron microscope,and the microscopic characteristics of the scaffold were analyzed.The mechanical properties,porosity,degradation rate and other parameters of the scaffold were tested and its physical properties were evaluated.By cultivating mouse preosteogenic cell lines,the biocompatibility of the scaffold was evaluated by cck-8 method,and the potential of the scaffold application in vivo was determined.Results:1.The scaffolds prepared from the above materials had the characteristics of uniform structure,stability,loose porosity,etc.The pore size and microscopic morphology observed by scanning electron microscopy could meet the needs of bone tissue engineering.2.It could be seccessful to optimize the biological activity of the material and load it with drugs.The mechanical properties,porosity and degradation rate of the scaffolds did not change significantly after modification,which all met the requirements of tissue engineering scaffolds.It was proved that the surface modification and loading drugs had no significant effect on the internal structure of the scaffold and did not change the physical properties;3CCK 8 test show that cells in the bracket of leaching solution can grow normally.Absorbance value of blank stents,modification and loading-drug scaffold has no obvious difference between each other.It indicates that the surface modification and drug loading of the scaffold in this study will not affect the biocompatibility of the scaffold,and the new surface osteogenic optimized scaffold prepared is safe and non-toxic,which can be further applied to the in vivo experiment to study its osteogenic potential.Conclusion:The modified silk fibroin/calcium silicate/chitosan bone tissue engineering scaffolds had good structure,surface morphology,pore size and porosity,which all met the needs of bone tissue engineering.Scaffolds could slowly degrade and release osteogenic drugs in the humoral environment,and the modified and drug-loaded scaffold had no cytotoxicity,so it could be applied to bone tissue engineering.