Osteogenic Property Of Hydroxyapatite/chitosan Bone Scaffolds Doped With Strontium And Icariin

Objectives Strontium and icariin doped hydroxyapatite/chitosan(IC-Sr HAP/CS)bone scaffold was prepared by freeze-drying technology,and the physicochemical properties,biocompatibility and in vitro osteogenic property of the scaffold were verified for its use on clinical bone defect reconstruction.Methods 1 Four bone scaffolds,including HAP/CS,Sr HAP/CS,IC-Sr HAP/CS and ICSr HAP/CS,were mixed by freeze-drying technique.The microstructure,micropore size,element composition,physical phase,anti-compressive pressure of the scaffolds and icariin release were examined by scanning electron mocroscope,energy dispersive spectrometer,X-ray diffraction,mechanical testing and high performance liquid chromatography respectively.2 The histocompatibility and cytocompatibility of bone scaffolds were detected by skin irritation test,hemolysis test,and adhesion and proliferation of MC3T3-E1 cells on scaffolds.Osteogenic differentiation of MC3T3-E1 cells were also examined by ALP activity and alizarin red staining to confirm the osteogenic property of the scaffolds.Results 1 Scanning electron microscope and energy dispersive spectrometer examination showed that the four scaffolds had similar microstructures and porosity(>85%),and the C,O,P,Ca and Sr elements were uniformly distributed in scaffolds.Anti-compressive pressure of four scaffolds were all larger than 1MPa and it dereased slightly in scaffolds with Sr(P<0.05).X-ray diffraction showed that HAP and Sr HAP crystals existed in Srdoped scaffolds.Icariin showed a burst release(20%)within the first 2 days,then icariin release slowed down and sustained for 90 days.2 No hemolysis and skin irritation reaction were observed in four scaffolds.Although IC-Sr HAP/CS scaffold showed no significant influence on MC3T3-E1 cell adhesion,it significantly promoted cell growth and proliferation(P<0.05),upregulated ALP activity(P<0.05)and increased extracellular matrix mineralization which is confirmed by much more red color stained mineralized nodules.Conclusion 1 The hydroxyapatite/chitosan bone scaffold materials with strontium and icariin(IC-Sr HAP/CS)were prepared.The addition of strontium and icariin had no significant effect on the microstructure,pore size and porosity of the material.Icariin was released slowly from the material in vitro for up to 90 days.2 IC-Sr HAP/CS bone scaffold material had good histocompatibility and cell compatibility,can effectively promote the proliferation and osteogenic differentiation of preosteoblasts,which was better than HAP/CS bone scaffold material with strontium or icariin.Figure 13;Table 10;Reference 108.