Schweiker Clara, Zankovic Sergej, Baghnavi Anna, Velten Dirk, Schmal Hagen, Thomann Ralf, Seidenstuecker Michael
G.E.R.N. Tissue Replacement, Regeneration and Neogenesis, Department of Orthopedics and Trauma Surgery, Medical Center-Albert-Ludwigs-University of Freiburg, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Freiburg, Germany.
Institute for Applied Biomechanics, Faculty of Mechanical and Process Engineering, Offenburg University, Offenburg, Germany.
Front Drug Deliv. 2024 May 17;4:1407304. doi: 10.3389/fddev.2024.1407304. eCollection 2024.
The core/shell 3D printing process using CPC and alginate is intended to create biodegradable scaffolds that have a similar stability to bone tissue and also offer sufficient and continuous antibiotic release. In this way, a patient-specific and patient-friendly process will be established, which should optimally support the human organism in its regeneration. To generate the best possible strength values, the printed scaffolds underwent various post-treatments and were then tested in a material test. The test methods included self-setting, storage in a drying cabinet with a water-saturated atmosphere at 37°C, followed by incubation in PBS, freeze-drying, and coating the samples with alginate. Additionally, a degradation test at pH 7.4 and pH 5 was carried out to test stability under conditions. It was shown that the untreated and freeze-dried samples failed at a maximum load of 30-700 N, while the remaining scaffolds could withstand a load of at least 2,000 N. At this failure load, most of the test series showed an average deformation of 43.95%. All samples, therefore, remained below the strength of cancellous bone. However, based on a 20% load after surgery, the coated scaffolds represented the best possible alternative, with a Young's modulus of around 1.71 MPa. We were able to demonstrate that self-setting occurs in core-shell printed CPC/alginate scaffolds after only 1 day, and that mass production is possible. By coating with alginate, the compressive strength could be increased without the need for additional post-treatment. The mechanical strength was sufficient to be available as a scaffold for bone regeneration and additionally as a drug delivery device for future applications and experiments.
使用磷酸钙骨水泥（CPC）和藻酸盐的核/壳3D打印工艺旨在制造具有与骨组织相似稳定性且能实现充分持续抗生素释放的可生物降解支架。通过这种方式，将建立一种针对患者且对患者友好的工艺，该工艺应能在人体再生过程中提供最佳支持。为了获得尽可能高的强度值，对打印的支架进行了各种后处理，然后在材料测试中进行测试。测试方法包括自固化、在37°C的水饱和气氛干燥箱中储存，随后在磷酸盐缓冲液（PBS）中孵育、冷冻干燥以及用藻酸盐对样品进行涂层处理。此外，还在pH 7.4和pH 5条件下进行了降解测试以检验稳定性。结果表明，未经处理和冷冻干燥的样品在最大负载30 - 700 N时失效，而其余支架至少能承受2000 N的负载。在这个失效负载下，大多数测试系列的平均变形为43.95%。因此，所有样品的强度均低于松质骨。然而，基于术后20%的负载，涂层支架是最佳选择，其杨氏模量约为1.71 MPa。我们能够证明，核/壳打印的CPC/藻酸盐支架仅在1天后就会发生自固化，并且大规模生产是可行的。通过用藻酸盐涂层，可以在无需额外后处理的情况下提高抗压强度。其机械强度足以作为骨再生支架，并额外作为未来应用和实验的药物递送装置。
