纳米磷酸钙/氧化锆骨组织工程支架体内降解的实验研究

目的研究纳米磷酸钙/氧化锆骨组织工程支架材料体内降解特性,为进一步构建组织工程化纳米人工骨提供研究依据。方法制作兔股部肌袋,将灭菌的纳米磷酸钙/氧化锆骨组织工程支架材料植入肌袋内,在植入4周、8周、12周、16周时取材通过大体、组织学、扫描电镜观察材料降解情况,同时将材料取出后煅烧,测量残余无机物含量,判断降解的量,同时进行X线衍射实验,测量残余材料的组成。结果材料植入8周内降解较慢,生物力学强度减低不明显,12周时降解加速,材料强度明显减低,16周时新骨形成明显,降解残余材料分布于新形成的骨组织内部,X线衍射发现12周时材料内有羟基磷灰石成分出现,提示有新骨形成,16周时羟基磷灰石成分明显增多。结论纳米磷酸钙/氧化锆骨组织工程支架材料具有较好的降解性和生物相容性,具有诱导成骨作用,可作为骨组织工程的支架材料。

Study on the degradation of nano-Zirconia/Calcium phosphate bone tissue engineering scaffold

Objective To study the degradation of nano-Zirconia/Calcium phosphate bone tissue engineering scaffold in vivo. Methods The Ca_3(PO_4)_2 artificial bone cells scaffold reinforced by nano-ZrO_2 after sterilization were transplanted intramuscularly in femoral region of the rabbits for 4,8,12,16 weeks. Degradation result was assessed by means of histology, scanning electron microscopy analysis. Determination of residual inorganic and else materials were completed through calcinations and X-ray diffraction. Results The rate of degradation was slow in 8 weeks after transplantation and its intensity of biomechanics did not reduced until to 12 weeks after transplantation. The creation of sufficient amount of new bone was seen until to 16 weeks after transplantation. The residual materials after dagradation distributed in new bone. Hydroxyapatite was found by X-ray diffraction in it at 12 weeks after transplantation. The result suggested new bone formation. By the end of 16 weeks, hydroxyapatite content increased significantly. Conclusion The hyper-porosity Ca_3(PO_4)_2 artificial bone cells scaffold reinforced by nano-ZrO_2 has ideal degradation rate, biocompatibility with great potential in inducing bone formation, and it is an ideal scaffold material for bone tissue engineering.