The Research On Preparation And Properties Of Antigen-extracted Heterologous Bone Scaffold Material

Objective:To compare the properties of the antigen-extracted heterologous bone by different methods to provide experimental data for the further researches of bone tissue engineering.Methods:Extract the fresh cancellous bones from the adult sheep vertebrae and form them into specific cylinders.Their long axis direction was same as orientation of trabeculae. Then divid the specimens into four groups randomly.The group A, group B and group C were classified as experimental groups. The group A was treated by some chemical agents such as the methanol/chloroform,30% hydrogen peroxide,etc. Then Calcine them for three hours. Group B was calcined directly after the simlpe treatments. Group C was processed by some chemical agents. Group D was classified as the control group which was processed by the simlpe treatments. Observe the properties of the heterologous bone by scanning electron microscope,the X-ray diffraction, X-ray elemental analysis, determination of nitrogen and examination of mechanical properties.Results:The experimental groups maintained natural network pore system in different degrees. The size of the large pore was between 50μm to 600μm and the small one was about 2μm. The porosity was between 55% to 70%. Hydroxyapatite(HAP) was the main composition of the group A and group B which were determined by X-ray diffraction, and a small amount of theβ-Tricalcium phosphate(β-TCP) was also determined. The ratios of calcium to phosphorus were (1.647±0.641):1,(1.637±0.096):1,(1.774±0.876):1 and (2.012±0.278):1. There were no significant differences among the four groups(P>0.05). In experimental groups, the nitrogen contents were 0%,0%,4.43% and 4.06%. The mechanical properties of group C was significantly better than the group A and group B.Conclusion:According the results, the physical and chemical methods of preparing the antigen-extracted bones were both good to keep the physical and chemical properties, that the three-dimensional space structures of the antigen-extracted bones were not damage greatly,and they had a great natural pore network system. Calcining can extract the antigen but damage the mechanical properties of the cancellous bones. Otherwise, the chemical agents can keep the mechanical properties good but left some antigen. The antigen-extracted heterologous bone scaffold material which were calcined can be used to be ideal scafford materials for future bone tissue engineering. Additionally, more investigations will be done to detect the biocompatibility of them.