Aydin Mehmet Serhat, Nicolae Carmen-Valentina, Campodoni Elisabetta, Mohamed-Ahmed Samih, Kadousaraei Masoumeh Jahani, Yassin Mohammed Ahmed, Gjerde Cecilie, Sandri Monica, Stancu Izabela-Cristina, Rashad Ahmad, Mustafa Kamal
Center of Translational Oral Research (TOR), Department of Clinical Dentistry, University of Bergen, 5009 Bergen, Norway.
Advanced Polymer Materials Group, Faculty of Chemical Engineering and Biotechnologies, National University of Science and Technology Politehnica Bucharest, Bucharest 011061, Romania.
ACS Appl Mater Interfaces. 2025 May 28;17(21):31411-31433. doi: 10.1021/acsami.5c03945. Epub 2025 May 15.
Extrusion-based 3D printing of thermoplastic polymers presents significant potential for bone tissue engineering. However, a key limitation is the frequent absence of filament porosity and the inherent osteoconductive properties. This study addresses these challenges by fabricating poly(lactide--trimethylene carbonate) (PLATMC) scaffolds with dual-scale porosity: macroporosity achieved through controlled filament spacing and microporosity introduced via NaCl leaching. The inclusion of NaCl generated rough, porous surfaces that were well-suited for dip-coating with magnesium-carbonate-doped hydroxyapatite (MgCHA), thereby imparting osteoconductive functionality. Thermal analysis revealed that salt incorporation had minimal impact on the polymer's thermal stability. Rheological studies and computational modeling indicated that NaCl reduced the viscosity under shear, leading to enhanced printability and faster extrusion speeds. After leaching, the scaffolds exhibited approximately 34% microporosity, which significantly increased water uptake and swelling capacity, despite the roughened surfaces slightly elevating hydrophobicity. The mechanical properties of PLATMC (with nonporous filaments) and p-PLATMC (with porous filaments) scaffolds showed a modulus of elasticity of 566 ± 118 and 101 ± 20 MPa, respectively, with strain values of 178 ± 54% and 84 ± 28%. Biological evaluations highlighted the compatibility of the p-PLATMC scaffolds. Cell viability and proliferation assays confirmed sustained cellular interaction over a 14 day period. Notably, alkaline phosphatase (ALP) activity was elevated in the porous scaffolds, and the MgCHA coating significantly enhanced mineral deposition by day 28, suggesting improved osteogenic potential. In conclusion, this study presents a robust strategy for fabricating 3D-printed PLATMC scaffolds with integrated filament porosity, offering a viable platform for osteoconductive coatings in bone tissue engineering applications.
基于热塑性聚合物的挤出式3D打印在骨组织工程方面具有巨大潜力。然而，一个关键限制是经常缺乏长丝孔隙率和固有的骨传导特性。本研究通过制造具有双尺度孔隙率的聚（丙交酯-碳酸三亚甲酯）（PLATMC）支架来应对这些挑战：通过控制长丝间距实现大孔隙率，并通过NaCl浸出引入微孔隙率。NaCl的加入产生了粗糙的多孔表面，非常适合用碳酸镁掺杂的羟基磷灰石（MgCHA）进行浸涂，从而赋予骨传导功能。热分析表明，盐的加入对聚合物的热稳定性影响最小。流变学研究和计算模型表明，NaCl降低了剪切下的粘度，从而提高了可打印性和挤出速度。浸出后，支架表现出约34%的微孔隙率，尽管粗糙的表面略微提高了疏水性，但显著增加了吸水率和溶胀能力。PLATMC（无孔长丝）和p-PLATMC（多孔长丝）支架的力学性能分别显示弹性模量为566±118和101±20 MPa，应变值分别为178±54%和84±28%。生物学评估突出了p-PLATMC支架的相容性。细胞活力和增殖试验证实了在14天内持续的细胞相互作用。值得注意的是，多孔支架中的碱性磷酸酶（ALP）活性升高，并且MgCHA涂层在第28天时显著增强了矿物质沉积，表明成骨潜力得到改善。总之，本研究提出了一种制造具有集成长丝孔隙率的3D打印PLATMC支架的稳健策略，为骨组织工程应用中的骨传导涂层提供了一个可行的平台。
