优化磷酸三钙/聚磷酸钙纤维/聚乳酸软骨组织工程支架材料的配比

Matching ratio of beta tricalcium phosphate/calcium polyphosphate fiber/polylactic acid composite scaffolds for cartilage tissue engineering

背景:前期实验显示,聚乳酸存在刚度差,降解缓慢,降解后期降解液明显偏于酸性,易在细胞培养时引起无菌性炎症反应等缺点。目的:在前期工作的基础上,优化聚乳酸支架材料实验方案和配比。方法:自制聚磷酸钙纤维和β-磷酸三钙为添加材料,聚左旋乳酸为基体材料,采用溶媒浇铸/粒子滤取技术与气体发泡相结合制备配比20/30/50磷酸三钙/聚磷酸钙纤维/聚乳酸软骨组织工程支架复合材料。结果与结论:①磷酸三钙/聚磷酸钙纤维/聚乳酸支架材料具有三维、连通、微孔网状结构,孔隙率在70%～95%。②孔隙率相近时,该支架材料的压缩模量比纯聚乳酸支架的压缩模量有了明显提高。③支架材料的降解率可通过加入聚磷酸钙纤维和支架的孔隙率加以调控。④β-磷酸三钙的加入使降解液pH值保持在6.0～7.0之间,避免了酸性降解产物引起的无菌性炎症反应。说明磷酸三钙/聚磷酸钙纤维/聚乳酸支架材料的物理力学性能和降解性能基本满足软骨组织工程的要求。

BACKGROUND： Nowadays, conventional polylactic acid scaffolds have many disadvantages, such as low stiffness, slow degradation, acid degradation solution and induced aseptic inflammation reaction. OBJECTIVE： Based on previous study, to optimize the matching ratio of β-tricalcium phosphate/calcium polyphosphate fiber/ polylactic acid scaffolds. METHODS： Taking β-tricalcium phosphate and calcium polyphosphate fiber as reinforced materials and polylactic acid as matrix materials in a ratio of 20/30/50, the composite scaffolds for cartilage tissue engineering were fabricated by solvent-casting particulate-leaching and gas foam methods, and their physical and mechanical properties and degradation rate and microstructure were tested. RESULTS AND CONCLUSION： The scaffolds with porosity of 70%-95% possessed three-dimensional, interconnecting, micro-hole network structure; Compared with comparable polylactic acid scaffolds, the scaffolds had higher compressive modulus; The degradation rate of scaffolds could be controlled by adding fiber and adjusting porosity of scaffolds; Adding β-tricalcium phosphate could make the pH value of degradation solution maintain at 6.0 to 7.0 and avoid aseptic inflammation reaction caused by acidic degradation products. Therefore, the physical and mechanical properties and degradation rate of the composite scaffolds can meet the demand of cartilage tissue engineering.