Study On Synthesis And Bone Repair Of Zein/Whitlockite/Levofloxacin Composite Scaffolds

Bone formation is a complex process in which bone regeneration and angiogenesis work together,angiogenesis is a prerequisite for bone regeneration.Therefore,there is a great demand for the next generation of orthopedic implants having osteoinductive and angiogenic capabilities in the field of bioengineering.Zein is a natural protein,both zein and its secondary products exhibit good biocompatibility,the 3D zein scaffold was shown to have appropriate porous structure and mechanical properties suitable for cell migration and tissue ingrowth.It also allowed blood vessels to form inside it,and it biodegraded well.Whitlockite(WH)is the second most abundant mineral in active bone,accounting for about 20% of bone minerals.In the early stage of biomineralization,WH is higher than hydroxyapatite(HA).Levofloxacin hydrochloride(LEVO)is a widely used broad-spectrum antibacterial drug in clinic.In this study,zein/WH porous composite scaffolds were prepared by simple salting-out method using zein and WH as raw materials,and on this basis,LEVO was adsorbed on the surface of zein/WH porous composite scaffolds to prepare non-toxic,biocompatible,vascularization-promoting,antibacterial properties and biodegradable zein/WH/LEVO porous scaffold material for bone tissue engineering.The physical and chemical properties of scaffolds were characterized,the morphology,elements and surface hydrophilicity of the materials were characterized by SEM,EDS and water contact angle.Using MC3T3-E1,HUVECs and MRSA as models,the biocompatibility and osteoinductivity were studied by thiazolidine blue,alizarin red staining and alkaline phosphatase assay.The angiogenic activity was measured by angiogenesis test.The antimicrobial properties of the scaffolds were investigated by agar diffusion method.The results show that the prepared porous scaffold materials have suitable pore structure,which is beneficial to angiogenesis.The zein/WH/LEVO porous scaffold material not only has significant pro-angiogenic ability,osteoinductivity but also excellent antibacterial properties.In vivo study in a SD IGS Rats bone defect model demonstrated significantly enhanced bone regeneration using the hybrid scaffold compared zein and zein/WH scaffolds.The results of the study are of great significance for the development of bone tissue engineering.