Chan Shareen S L, Black Jay R, Franks George V, Heath Daniel E
Chemical Engineering, The University of Melbourne, VIC 3010, Australia.
School of Geography, Earth and Atmospheric Sciences, The University of Melbourne, VIC 3010, Australia; Trace Analysis for Chemical, Earth and Environmental Sciences (TrACEES) Platform, The University of Melbourne, VIC 3010, Australia.
Biomater Adv. 2025 Apr;169:214149. doi: 10.1016/j.bioadv.2024.214149. Epub 2024 Dec 9.
Sacrificial templating offers the ability to create interconnected pores within 3D printed filaments and to control pore morphology. Beta-tricalcium phosphate (TCP) bone tissue engineering (BTE) scaffolds were fabricated with multiscale porosity: (i) macropores from direct ink writing (DIW, a material extrusion 3D printing technique), (ii) micropores from oil templating, and (iii) smaller micropores from partial sintering. The hierarchically porous scaffolds possessed a total porosity of 58-70 %, comprising 54-63 % interconnected open pores. The in vitro results demonstrated that scaffolds with macroporosity promoted human osteoblast growth more than scaffolds with only microporosity. The elongated pores from the capillary suspension filament microstructure induced greater cell spreading than the sphere-like pores from the emulsion. Overall, the hierarchically porous scaffold with capillary suspension TCP filaments provided a superior microenvironment for significantly higher cell viability and proliferation than the other scaffolds, including a poly(ε-caprolactone) (PCL) control, a material currently used clinically as porous BTE scaffolds. The cellular response was further enhanced when macropore size was in the range of 570-590 μm. Therefore, the hierarchically porous scaffolds in this study are promising as BTE scaffolds, and the reported process of DIW of oil-templated colloidal pastes is a feasible strategy with potential for further customization.
牺牲模板法能够在3D打印长丝中创建相互连接的孔隙，并控制孔隙形态。采用多尺度孔隙率制备了β-磷酸三钙（TCP）骨组织工程（BTE）支架：（i）通过直接墨水书写（DIW，一种材料挤出3D打印技术）形成大孔，（ii）通过油模板法形成微孔，（iii）通过部分烧结形成更小的微孔。这种具有分级孔隙结构的支架总孔隙率为58-70%，其中相互连接的开孔占54-63%。体外实验结果表明，具有大孔隙率的支架比仅具有微孔的支架更能促进人成骨细胞的生长。毛细管悬浮长丝微观结构产生的细长孔隙比乳液产生的球形孔隙诱导更大的细胞铺展。总体而言，具有毛细管悬浮TCP长丝的分级多孔支架为细胞提供了一个优越的微环境，与其他支架相比，其细胞活力和增殖能力显著更高，这些支架包括聚（ε-己内酯）（PCL）对照支架，一种目前临床上用作多孔BTE支架的材料。当大孔尺寸在570-590μm范围内时，细胞反应进一步增强。因此，本研究中的分级多孔支架有望成为BTE支架，并且所报道的油模板胶体糊剂的DIW工艺是一种可行的策略，具有进一步定制的潜力。
