基于3D打印技术SF/PVA/HA复合骨支架的制备及表征

Preparation and characterization of SF/PVA/HA composite bone scaffold based on 3D printing

寻找理想的骨修复生物材料是治疗骨缺损疾病的首要任务,本研究选择丝素蛋白(SF)、聚乙烯醇(PVA)和羟基磷灰石(HA)作为组织工程骨支架修复材料。设计正交试验探究出材料最佳配比:SF溶液浓度为3%、SF与PVA质量比为1∶5、SF/PVA水凝胶与HA的比为1.6 mL∶1 g;此条件下,骨支架的机械性能最佳。采用3D打印技术制备出多孔骨支架,研究骨支架的结构形貌,分析支架材料的复合机理,利用体外细胞实验评估复合材料毒性。结果显示,骨支架成型效果好,孔连通性好,孔隙率高于55%并保持良好的力学性能。SF与PVA形成复合凝胶过程中SF分子和PVA分子间发生了一定程度的相互作用,有良好的结合性,而SF/PVA凝胶与HA为简单物理混合无相互作用。细胞毒性实验结果表明,细胞生长良好,复合材料无细胞毒性。利用3D打印技术制备SF/PVA/HA骨支架的机械与生物性能满足松质骨的要求,对治疗骨缺损具有一定应用价值。

Searching the ideal bone repair biomaterials is a top priority for the treatment of bone defect diseases.A silk fibroin(SF),a polyvinyl alcohol(PVA)and a hydroxyapatite(HA)are selected as tissue engineered bone for supporting repair materials in this study.The optimum ratio of the material is investigated by designing orthogonal experiment.The investigated results show that bone scaffolds have the best mechanical properties when the concentration of SF solution is 3%,the mass ratio of SF to PVA,and the ratio of SF/PVA hydrogel to HA are 1∶5,and 1.6 mL∶1 g,respectively.Then,3 D printing technology is used to prepare porous bone scaffolds.The structure and morphology of bone scaffolds are studied,the composite mechanism of the scaffold materials is analyzed,and the toxicity of composite materials is evaluated using in vitro cell experiments.The results show that the bone scaffold has good forming effect,good pore connectivity,porosity above 55%and good mechanical properties.A certain degree of interaction between SF and PVA molecules occurred during the formation of SF and PVA hydrogels and good bonding while SF/PVA hydrogel and HA are simple physical mixtures without interaction.The results of cytotoxicity test show that the cells grew well and the composites has no cytotoxicity.The mechanical and biological properties of SF/PVA/HA bone scaffolds prepared by 3 D printing technology can meet the requirements of cancellous bone,and have certain practical value for the treatment of bone defects.