Department of Materials Science and Engineering, Sharif University of Technology, Tehran, Iran.
Department of Materials Science and Engineering, Sharif University of Technology, Tehran, Iran.
J Mech Behav Biomed Mater. 2024 Jan;149:106239. doi: 10.1016/j.jmbbm.2023.106239. Epub 2023 Nov 15.
The ease of processing and biocompatibility of polylactic acid (PLA) have made it a widely used material for fused deposition modeling (FDM)-based 3D printing. In spite of this, PLA suffers from some limitations for its extensive use in tissue engineering applications, including poor wettability, low degradation rate, and insufficient mechanical properties. To address the previously mentioned limitations, this study examined how combining in-process cold atmospheric plasma treatment with the inclusion of CaCO influences the properties of FDM-printed PLA scaffolds. Differential scanning calorimetry results showed that by incorporating CaCO micro-particles into the PLA matrix, heterogeneous nucleation promoted the matrix's crystalline content. Scanning electron microscopy analysis revealed that the surface of the PLA-CaCO scaffold exhibited increased roughness and improved interlayer bonding after undergoing plasma treatment. Atomic force microscopy revealed a significant (up to 80-fold) increase in the roughness value of PLA scaffolds after the incorporation of CaCO and subsequent cold plasma treatment. Furthermore, X-ray photoelectron spectroscopy analysis indicated that atmospheric plasma treatment substantially increased the presence of oxygen-containing bonds, leading to a significant reduction in the water contact angle, which decreased from 89° to 37°. According to the tensile test, the tensile modulus (634.1 MPa) and ultimate tensile strength (25.4 MPa) of PLA were markedly increased and reached 914.3 and 37.2 MPa, respectively, for the plasma-treated PLA-CaCO (PT-PLA-CaCO). Additionally, the in-vitro degradation test showed that PT-PLA-CaCO scaffold exhibited higher degradation rate compared to the PLA-CaCO sample. Based on the obtained results, it appears that in-process cold atmospheric plasma treatment could serve as an efficient and straightforward method to enhance the properties of 3D-printed composite parts, particularly for tissue engineering applications.
聚乳酸（PLA）易于加工和生物相容性使其成为熔融沉积建模（FDM）基础 3D 打印的广泛应用材料。尽管如此，PLA 在组织工程应用中仍存在一些限制，包括润湿性差、降解率低和机械性能不足。为了解决之前提到的限制，本研究探讨了在加工过程中结合冷大气压等离子体处理与 CaCO 掺入如何影响 FDM 打印 PLA 支架的性能。差示扫描量热法结果表明，通过将 CaCO 微球掺入 PLA 基质中，异相成核促进了基质的结晶含量。扫描电子显微镜分析表明，经过等离子体处理后，PLA-CaCO 支架的表面粗糙度增加，层间结合得到改善。原子力显微镜显示，在掺入 CaCO 并随后进行冷等离子体处理后，PLA 支架的粗糙度值显著增加（高达 80 倍）。此外，X 射线光电子能谱分析表明，大气压等离子体处理大大增加了含氧键的存在，导致水接触角显著降低，从 89°降低到 37°。根据拉伸试验，PLA 的拉伸模量（634.1 MPa）和拉伸强度（25.4 MPa）显著增加，等离子体处理的 PLA-CaCO（PT-PLA-CaCO）分别达到 914.3 MPa 和 37.2 MPa。此外，体外降解试验表明，PT-PLA-CaCO 支架的降解速率高于 PLA-CaCO 样品。根据获得的结果，似乎在加工过程中冷大气压等离子体处理可以作为一种有效且简单的方法来增强 3D 打印复合部件的性能，特别是在组织工程应用中。
