Preparation And Biological Performance Of Derived Bone Graft Surface-modified By Biomemtic Deposition

ObjectiveBone graft is the most commonly used method of repairing maxillofacial bone defects.Xenogeneic bone,(such as cattle,sheep,pigs and other mammals)cancellous bone is a kind of inorganic bone stent,internal structure and composition are very similar to the human bone,and a wide range of sources,is a good raw material for the preparation of bone graft material.The xenogeneic bone can be used to extracted the antigen by different methods to obtain a bio-derived bone scaffold with only inorganic components,which is a highly promising bone graft material.However,the main components of the bio-derived bone scaffolds are hydroxyapatite after antigens treatment,which is stable and hard to degrade and cannot provide sufficient raw material for osteogenesis in the early stage of implantation,thus affecting its osteogenic activity.Therefore,in order to make it have better osteogenic activity,the need to modify the surface of the derived bone scaffold.At present,the hydroxyapatite surface modification method is numerous,most of the method is very complex,and the conditions of surface modification are harsher.Therefore,to explore a simple,easy to achieve bio-derived bone scaffold surface modification method is very necessary.Method1.Take yak cancellous bone,in methanol/ chloroform mixture and 30% hydrogen peroxide solution alternately soaking,extract the antigen,and then calcined at 900? for 2 hours to prepare the calcined derived bone scaffold,and the structure and composition of the material are characterized by SEM,XRD,FTIR.2.The prepared bone scaffolds were immersed in 2 times simulate body fluid at 37 ? for bionic deposition.The microstructure and composition of the materials was studied by SEM,XRD and FTIR for 1 week,3 weeks and 5 weeks respectively.3.The osteoblasts were induced by MC3T3-E1 cell line in vitro,and co-cultured with each group of materials to observe the early adhesion,spreading and proliferation of osteoblasts on the surface of the materials.To study the alkaline phosphatase activity of osteoblast on the alkaline phosphatase and to analyze the early in vitro osteogenic properties of the different surface modified materials.Result1.The chemical and physical combination method can completely extract the antigenic components in xenogeneic cancellous bone,get the bone scaffold material.It has a porous internal structure,which's composition is confirmed to be hydroxyapatite.2.After the biomimetic deposition of the derived bone scaffold material,the mineralized sediments formed on the surface of the bone scaffold,and the sediments are gradually increasing with the immersion time.When the bionic sedimentation was 5 weeks,the sedimentation area was the largest and the distribution of the sediment was the most uniform.XRD and FTIR tests confirmed that the sediments formed on the surface of the material were carbonate-based and structurally complex bony apatite.3.Compared with the bone scaffolds between the surface of biomaterials after bionic deposition and the derived bone without bionic deposition,the osteoblasts adhered and proliferated more on the surface of the bone scaffold with bionic deposits,and the expression of ALP activity in osteoblasts was stronger,and on the surface of the material,osteoblasts spread in good condition,pseudo-foot enough to stretch around.ConclusionThe bone scaffolds can be prepared by chemical and physical combined method.After 2 times of biomimetic fluid deposition,the surface of the material can be deposited to produce bone-like apatite,and the derived bone scaffold material after immersion for 5 weeks can promote osteoblast adhesion spreads and proliferates on the surface of the material earlier,and the cells are functioning well.