PLLA/β-TCP支架表面多孔结构的构建及其对细胞黏附的影响

Construction of porous structure on the surface of PLLA/β-tricalcium scaffold and its effect on cell adhesion

目的通过NaOH溶液的简单处理构建3D打印PLLA/β-TCP骨组织工程支架表面多孔结构,增加支架的粗糙度和亲水性,促进支架表面的细胞黏附。方法通过3D打印熔融沉积成型技术制备PLLA/β-TCP网状支架,并通过NaOH蚀刻的方法进行支架的粗糙化改性,依据支架表面微观形貌、能谱、接触角、力学、细胞黏附等观察NaOH浓度、时间两项反应参数对支架的影响。结果通过熔融沉积成型技术制备的PLLA/β-TCP复合支架存在预先设置的网状结构;经NaOH蚀刻构建了兼有宏观和微观空隙的多孔形态。NaOH浓度、时间中任意一种参数的增加都会导致支架表面微观孔隙的孔径、孔密度增加。NaOH处理参数为0.1 mol/L(9 h)时,可显著减小支架表面水接触角,且对支架的压缩强度无显著影响。体外细胞检测显示,经NaOH蚀刻后的表面多孔复合支架在骨髓间充质干细胞(BMSCs)的黏附增殖上更具优势。结论用NaOH处理3D打印PLLA/β-TCP骨组织工程支架可有效改善支架表面形态,优化该类支架的亲水性及细胞黏附。

Objective To construct a 3D printed PLLA/β-tricalcium(PLLA/β-TCP)bone tissue engineering scaffold surface porous structure through simple treatment with NaOH solution,increase the roughness and hydrophilicity of the scaffold,and promote cell adhesion on the scaffold surface.Methods The PLLA/β-TCP mesh scaffold was prepared by 3D printing melt deposition molding technology,and the scaffold was roughed by NaOH etching.The effects of NaOH concentration and time on the scaffold were observed according to the microstructure,energy spectrum,contact angle,mechanics,and cell adhesion of the scaffold.Results The PLLA/β-TCP composite scaffold constructed by melt deposition technology had a pre-set porous structure,and the pores were interconnected.After NaOH etching,a porous structure with both macroscopic and microscopic pores was formed.The increase in any of the NaOH concentration and time parameters would lead to the increase of pore diameter and surface roughness.When the NaOH treatment parameter was 0.1 mol/L(9 h),it could significantly reduce the water contact angle on the surface of the scaffold,and had no significant effect on the compressive strength of the scaffold.In vitro cell testing showed that the surface porous composite scaffold etched with NaOH had more advantages in the adhesion and proliferation of BMSCs.Conclusion Using NaOH to process 3D printing of PLLA/β-TCP bone tissue engineering scaffolds can effectively improve the surface morphology of the scaffold,and optimize its hydrophilicity and cell adhesion.