三维打印羟基磷灰石/磷酸三钙骨支架工艺中粉体材料组分比及黏结剂对骨支架性能的影响

Effects of composition ratios of powder materials and adhesive on the properties of 3DP HA/β-TCP bone scaffold

笔者研究了胶水选用及粉材组分对三维打印羟基磷灰石/磷酸三钙(HA/β-TCP)骨支架性能的影响。为了改善骨支架的力学性能和生物兼容性,分别选用磷酸和聚乙烯醇作为黏结剂,使用Zprinter 250三维打印机制备了不同HA/β-TCP质量配比(100∶0、80∶20、60∶40及40∶60)的骨支架。通过孔隙率测量、吸水性实验、抗压强度试验、电镜扫描及细胞培养等多种实验方法,分别从连通性、微观结构、表面特性、力学性能及生物兼容性等方面分析了不同胶水及组分比例制备的骨支架性能。结果表明:使用磷酸作为黏结剂的骨支架,不论从微观结构还是生物兼容性和力学强度,其性能均优于聚乙烯醇制备的骨支架。当粉材中HA与β-TCP的比为60∶40时,磷酸骨支架抗压强度取得最大值(4.8 MPa),此时其弹性模量为200 MPa,此外,细胞培养实验表明HA与β-TCP的比为60∶40的磷酸骨支架在促细胞增殖生长方面的表现也最优。因此,后续的临床试验中可选用磷酸作为黏结剂,而HA与β-TCP比为60∶40的骨支架更能促进细胞的生长和增殖。

Abstract：The paper experimentally studied the effect of binder selection and hydroxyapatite / β-tricalciumphosphate （HA/ β-TCP） ratio on 3D printed scaffold properties.In order to improve mechanical propertiesand biocompatibility of the 3D printed scaffold,scaffolds with various HA/ β-TCP ratios （100 ∶ 0,80 ∶ 20,60 ∶ 40 and 40 ∶ 60） were printed by Zprinter250 using phosphate acid and polyvinyl alcohol as binder,respectively.Through measuring the scaffold porosity, surface hydrophilia, scaffold compressive strengthand experiments of scanning electron microscope （SEM） and murine bone marrow stem cells （mBMSC）culture,the connectivity,micro-structure,surface property,mechanical characteristics and biocompatibilityof the printed scaffolds were evaluated in the paper. The experiments results revealed that both themechanical properties and biocompatibility of scaffolds printed using phosphate acid as binder were betterthan ones using polyvinyl alcohol.When the HA/ β-TCP ratio were 60 ∶ 40 （H6040） the compressivestrength of the scaffold printed using phosphate acid reached maximum （4- 8 MPa）,while Young Moduluswas 200 MPa. At the same time, in the mBMSC culture experiment, the H6040 scaffold also show asuperior performance in promoting the cell growth and proliferation.Therefore,the phosphate acid could beused as an optimal alternative in the followed clinic test. And scaffold with 60 ∶ 40 HA/ β-TCP ratioperformed better in promoting cell growth and proliferation.