组织工程多孔生物材料的制备及表征

Preparation and characteristics of micro porous biomaterials of bone tissue engineering

目的制备适合新骨长入的孔隙率、孔隙尺寸和结构的多孔磷酸钙组织工程支架材料。方法通过湿法共沉淀法合成羟基磷灰石(HA)/磷酸三钙(TCP)双相粉末作为起始粉末,分别采用有机泡沫浸浆法和适当的致孔剂加入磷酸钙骨水泥中,分别制备多孔磷酸钙陶瓷和多孔磷酸钙骨水泥,并测量多孔隙率,采用扫描电镜观测试样的形貌和孔隙结构,利用X射线衍射分析磷酸钙的相成分。结果多孔磷酸钙陶瓷和磷酸钙骨水泥的孔隙率分别为72%和67%;孔隙尺寸主要分布在200～280μm;孔壁上分别存在大量孔径仅为数微米至数十微米的微孔,为微孔隙间的贯通提供了可能性;X射线衍射结果证明多孔磷酸钙陶瓷的组成包括HA和β-TCP,而多孔磷酸钙骨水泥的主要成分均为HA,β-TCPandβ-TCP。结论本试验制备的多孔磷酸钙陶瓷和多孔磷酸钙骨水泥具有适合新骨长入的孔隙直径和孔隙率,具有良好的生物相容性。

Objective To synthesize hydroxyapatite/tricalcium phosphate biphasic powder as a tissue engineering mate- rial. Methods The hydroxyapatite （HA）/tricalcium phosphate （TCP） were synthesized by the wet co-preclpitation method as starting powder. Appropriate progeny were added into the calcium phosphate cement （ CPC ） to fabricate the porous calcium phos- phate （ CaP ） ceramics and porous CPC via polymer sponge immersion （ or impregnation ） method. The porosity of CaP ceramics and CPC were measured. The morphology and structure of CaP ceramics and CPC were observed by scanning electronic microsco- py （ SEM ）. The phase composition of CaP ceramics and CPC were analyzed by X-ray diffraction （ XRD ）. Results The present results showed that the porosity of CaP ceramics was 72% and the porosity of CPC was 67%. The pore size of CaP ceramics and CPC were distributed at 100-500μm. There were amounts of micro-pore, whose size were ranged in several micrometers grade on the pore wall. They could provide the possibility to form the connective porous structure in CaP ceramics and CPC. The results of XRD demonstrated that CaP ceramics comprised HA and β-TCP; while CPC comprised HA, β-TCP and β-TCP. Conclusion These three kinds of CaP salt have been utilized in clinic successfully and have excellent biocompatibility. The CaP ceramics and CPC possess the appropriate pore size and porosity, which are fit for in-growth of new bones.