Ice Template Preparation And Biological Evaluation In Vivo Of Multi-scale Micro-nano Structure Composite Scaffold

Hydroxyapatite(HA) is similar with bone matrix inorganic composition, exhibiting excellent biocompatibility with the soft tissues such as skin, muscle and gum.Poly(lactic-co-glycolic acid,PLGA) is commonly used in tissue engineering because of good biocompatibility and innocuity.The human resource bone morphogenetic protein-2(rhBMP-2)can induce the mesenchymal stem cells transfer to cartilage cells and osteoblasts.The nano-hydroxyaoatite was prepared by chemical precipitation method,presenting a good bone integration ability, present a larger surface area.The PLGA microspheres and PLGA microspheres which contained the rhBMP-2 were characterized by SEM and encapsulation rate measurement.Results show that there was no evident difference in surface morphology and size while the diameter is 5 ?m and the entrapment efficiency of the PLGA&rhBMP-2 microspheres reached about 52%.Micro-nano structure scaffold was prepared by ice-template method and characterized by SEM,porosity measurement and compression strength detection.Results show that the scaffolds have obvious layered structure and good porosity which highly reached 87%.In addition,the compressive strength is 100 KPa.Rat skull critical deficiency mode is a ordinary standard animal mode and the dificiency mode was created by forming a 5mm-diameter circular dificiency in the skull of 8-week old male rat.Then H&E staining and Micro-CT were conducted to observe materials and tissue 4w,8w and 12 w later.Results show that the scaffold with PLGA&rhBMP-2microspheres perform good biocompatibility and promote bone repairing better.