3D打印高密度聚乙烯支架表面涂层的性能

Properties of surface coatings for 3D printed high density polyethylene scaffolds

背景:高密度聚乙烯常用作颅颌面骨缺损的修复材料,然其制备方式及表面活性仍需进一步改进。目的:优化高密度聚乙烯制备方法,改善高密度聚乙烯表面活性。方法:基于挤出式3D打印技术制备高密度聚乙烯支架,将支架依次浸入多巴胺溶液、模拟体液中进行聚多巴胺、羟基磷灰石涂层。表征涂层前后支架的微观形貌、亲水性和压缩模量。在支架表面分别接种小鼠胚胎成骨前体细胞MC3T3-E1和人脐静脉内皮细胞,评估涂层前后支架的细胞相容性、早期成骨活性和促血管活性。结果与结论:①3D打印的高密度聚乙烯支架纤维排列规则,孔隙均匀;表征结果显示,支架表面聚多巴胺、羟基磷灰石改性成功;与未改性支架相比,聚多巴胺涂层与聚多巴胺+羟基磷灰石涂层改性后的支架表面水接触角明显减小(P<0.05),压缩模量未发生明显变化;②与未改性支架相比,聚多巴胺涂层与聚多巴胺+羟基磷灰石涂层改性后的支架可促进MC3T3-E1细胞、人脐静脉内皮细胞的黏附(P<0.05),且双涂层改性组促细胞黏附优于单涂层改性组(P<0.05);与未改性支架相比,聚多巴胺涂层与聚多巴胺+羟基磷灰石涂层改性后的支架可促进MC3T3-E1细胞、人脐静脉内皮细胞的增殖(P<0.05),且双涂层改性组促细胞增殖优于单涂层改性组(P<0.05);与未改性支架相比,聚多巴胺涂层与聚多巴胺+羟基磷灰石涂层改性后的支架可促进MC3T3-E1细胞的成骨分化(P<0.05),提高人脐静脉内皮细胞血管生成因子CD31的表达,其中以双涂层改性组效果更明显;③结果表明,经聚多巴胺、羟基磷灰石涂层后,3D打印高密度聚乙烯支架具有良好的细胞相容性、早期促成骨活性和促血管活性。

BACKGROUND:High density polyethylene has been widely used as a repair material for cranial and maxillofacial bone defects,but its preparation method and surface activity still need further improvement.OBJECTIVE:To optimize the preparation method of high density polyethylene and improve the surface activity of high density polyethylene.METHODS:The high density polyethylene scaffolds were prepared by extrusion 3D printing technology,and the scaffolds were immersed in dopamine solution and simulated body fluid successively to be coated with polydopamine and hydroxyapatite.The microstructure,hydrophilicity and compression modulus of the scaffolds before and after coating were characterized.Mouse embryonic osteogenic precursor cells(MC3T3-E1)and human umbilical vein endothelial cells were inoculated on the surface of the scaffold to evaluate the cytocompatibility and early osteogenic and angiogenic differentiation of the scaffold before and after coating.RESULTS AND CONCLUSION:(1)The 3D printed high density polyethylene scaffold’s fibers were arranged regularly and pores were uniform.Characterization results showed that polydopamine and hydroxyapatite coatings were successful on the surface of the scaffolds.Compared with the unmodified scaffold,the surface water contact angle of the scaffold modified with polydopamine coating and polydopamine+hydroxyapatite coating decreased significantly(P<0.05),and the compressive modulus did not change significantly.(2)Compared with the unmodified scaffold,the modified scaffold with polydopamine coating and polydopamine+hydroxyapatite coating could promote the adhesion of MC3T3-E1 cells and human umbilical vein endothelial cells(P<0.05).The cell adhesion promoting effect of double coating modified group was better than that of single coating modified group(P<0.05).Compared with the unmodified scaffold,the modified scaffold with polydopamine coating and polydopamine+hydroxyapatite coating could promote the proliferation of MC3T3-E1 cells and human umbilical vein endothelial cells(P<0.05).The proliferation promoting effect of double coating modified group was better than that of single coating modified group(P<0.05).Compared with unmodified scaffolds,the scaffolds modified with polydopamine coating and polydopamine+hydroxyapatite coating could promote the osteogenic differentiation of MC3T3-E1 cells(P<0.05),and increase the expression of angiogenic factor CD31 in human umbilical vein endothelial cells.The double-coating modified group was more obvious.(3)The results showed that the high density polyethylene scaffolds coated with polydopamine and hydroxyapatite based on 3D printing technology have good cytocompatibility and early osteogenic and angiogenic differentiation ability.