Alamán-Díez Pilar, García-Gareta Elena, Napal Pedro Francisco, Arruebo Manuel, Pérez María Ángeles
Multiscale in Mechanical and Biological Engineering, Instituto de Investigación en Ingeniería de Aragón (I3A), Instituto de Investigación Sanitaria Aragón (IIS Aragón), University of Zaragoza, 50018 Zaragoza, Spain.
Division of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, University College London, London WC1E 6BT, UK.
Materials (Basel). 2022 Mar 31;15(7):2572. doi: 10.3390/ma15072572.
Creating biofunctional artificial scaffolds could potentially meet the demand of patients suffering from bone defects without having to rely on donors or autologous transplantation. Three-dimensional (3D) printing has emerged as a promising tool to fabricate, by computer design, biodegradable polymeric scaffolds with high precision and accuracy, using patient-specific anatomical data. Achieving controlled degradation profiles of 3D printed polymeric scaffolds is an essential feature to consider to match them with the tissue regeneration rate. Thus, achieving a thorough characterization of the biomaterial degradation kinetics in physiological conditions is needed. Here, 50:50 blends made of poly(ε-caprolactone)-Poly(D,L-lactic-co-glycolic acid (PCL-PLGA) were used to fabricate cylindrical scaffolds by 3D printing (⌀ 7 × 2 mm). Their hydrolytic degradation under static and dynamic conditions was characterized and quantified. For this purpose, we designed and in-house fabricated a customized bioreactor. Several techniques were used to characterize the degradation of the parent polymers: X-ray Photoelectron Spectroscopy (XPS), Gel Permeation Chromatography (GPC), Scanning Electron Microscopy (SEM), evaluation of the mechanical properties, weigh loss measurements as well as the monitoring of the degradation media pH. Our results showed that flow perfusion is critical in the degradation process of PCL-PLGA based scaffolds implying an accelerated hydrolysis compared to the ones studied under static conditions, and up to 4 weeks are needed to observe significant degradation in polyester scaffolds of this size and chemical composition. Our degradation study and characterization methodology are relevant for an accurate design and to tailor the physicochemical properties of polyester-based scaffolds for bone tissue engineering.
创建具有生物功能的人工支架有可能满足骨缺损患者的需求，而无需依赖供体或自体移植。三维（3D）打印已成为一种很有前景的工具，通过计算机设计，利用患者特定的解剖数据，高精度地制造可生物降解的聚合物支架。实现3D打印聚合物支架的可控降解特性是使其与组织再生速率相匹配时需要考虑的一个基本特征。因此，需要全面表征生物材料在生理条件下的降解动力学。在此，使用聚（ε-己内酯）-聚（D，L-乳酸-乙醇酸共聚物）（PCL-PLGA）制成的50:50共混物通过3D打印制造圆柱形支架（⌀ 7×2毫米）。对其在静态和动态条件下的水解降解进行了表征和量化。为此，我们设计并在内部制造了一个定制的生物反应器。使用了几种技术来表征母体聚合物的降解：X射线光电子能谱（XPS）、凝胶渗透色谱（GPC）、扫描电子显微镜（SEM）、力学性能评估、重量损失测量以及降解介质pH值监测。我们的结果表明，流动灌注在基于PCL-PLGA的支架降解过程中至关重要，这意味着与在静态条件下研究的支架相比水解加速，并且需要长达4周的时间才能观察到这种尺寸和化学成分的聚酯支架出现明显降解。我们的降解研究和表征方法对于准确设计和定制用于骨组织工程的聚酯基支架的物理化学性质具有重要意义。
