Ferrández-Montero A, Lieblich M, Sanchez-Herencia A J, Detsch R, Boccaccini A R, Ferrari B
Instituto de Cerámica y Vidrio (ICV-CSIC), Spain.
Centro Nacional de Investigaciones Metalúrgicas (CENIM-CSIC), Spain.
Colloids Surf B Biointerfaces. 2025 Nov;255:114906. doi: 10.1016/j.colsurfb.2025.114906. Epub 2025 Jun 24.
The PLA/Mg composite has been proposed as a promising new biodegradable biomaterial with interesting properties for use in a number of biomedical applications. However, its processing is still highly problematic mainly due to its high reactivity and biodegradability. Recently the benefit of a new processing route based on a colloidal approach has been proposed based on the particle surface modification with different polyelectrolytes. Colloidal route improves the mechanical and biodegradation properties as a consequence of the creation of a strong polymer-metal interface and an increase of the particle dispersion. In this paper, we demonstrated these benefits compared with the most widespread mixing technique, the thermal extrusion. Firstly, PLA/Mg composite was evaluated in terms of its thermal behavior to determine the processing parameters required. After processing, the colloidal composite presents a covalent bond between the metallic particle and thepolymer when produced by the process of reactive extrusion, as determined by FTIR-ATR. This results in an improvement of the dispersion and the mechanical properties, reaching a maximum compressive strength of 130 MPa and an elastic modulus of 2150 MPa with 25 vol.% Mg particle loading. The colloidal processing also interferes in the biodegradation properties of PLA/Mg, decreasing the H release by 35 %, increasing the degradation time, and producing materials that degrade more homogeneously. Furthermore, the colloidal composite was found to be cytocompatible as the tests carried out with the ST2 bone marrow stromal cell line showed no negative effects. The cells exhibited a three-dimensional spreading morphology on the materials.
聚乳酸/镁复合材料被认为是一种很有前景的新型可生物降解生物材料，具有诸多有趣的特性，可用于多种生物医学应用。然而，其加工过程仍存在很大问题，主要是由于其高反应性和生物降解性。最近，基于用不同聚电解质对颗粒表面进行改性，提出了一种基于胶体方法的新加工路线的优势。由于形成了强大的聚合物-金属界面并增加了颗粒分散性，胶体路线改善了材料的机械性能和生物降解性能。在本文中，我们将这些优势与最广泛使用的混合技术——热挤出进行了比较。首先，对聚乳酸/镁复合材料的热行为进行了评估，以确定所需的加工参数。加工后，通过傅里叶变换红外光谱-衰减全反射（FTIR-ATR）测定，胶体复合材料在通过反应挤出工艺生产时，金属颗粒与聚合物之间存在共价键。这导致分散性和机械性能得到改善，在镁颗粒含量为25体积%时，最大抗压强度达到130兆帕，弹性模量达到2150兆帕。胶体加工还会影响聚乳酸/镁的生物降解性能，使氢气释放量减少35%，延长降解时间，并使材料降解得更均匀。此外，由于对ST2骨髓基质细胞系进行的测试表明没有负面影响，所以发现胶体复合材料具有细胞相容性。细胞在材料上呈现出三维铺展形态。
