Advanced Biomaterials and Tissue Engineering Center, Huazhong University of Science and Technology, Wuhan, China.
Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China.
J Biomed Mater Res A. 2019 Nov;107(11):2512-2521. doi: 10.1002/jbm.a.36757. Epub 2019 Jul 26.
In this study, we have successfully fabricated magnesium (Mg) substituted hydroxyapatite nanocomposites (Mg-HA) by utilizing type I collagen (COL I) and citric acid (CA) through a bitemplate-induced biomimetic mineralization approach. The obtained composite nanoparticles were subsequently mixed with chitosan (CHI) and gelatin (Gel) to prepare porous scaffolds with interconnected structures by three-dimensional (3D) printing technique. The Mg-HA powders and composite scaffolds were characterized. The results showed that the substitution of Mg for Ca ions reduced the crystallinity of HA crystals, but did not significantly affect the size and structure of the nanocomposites. The morphology of Mg-HA scaffolds turned smoother compared with the HA scaffolds with Mg substitution. Furthermore, the biocompatibility of Mg-HA composite scaffolds was evaluated by metal ion release, cell attachment, proliferation, and differentiation of MC3T3-E1 cells. According to the results, as the more Ca was substituted by Mg , the more Mg was released from the samples and the pH in cultured medium was more acidic. It was suggested that Mg-HA scaffolds presented higher cell attachment, proliferation rate, increased expression of alkaline phosphatase (ALP) activity and osteogenic related gene, including osteocalcin (OCN), runt-related transcription factor 2 (RUNX2), and COL I. Therefore, it was indicated that the 3D printed Mg-HA composite scaffolds with excellent biocompatibility and bioactivity were a potential candidate in bone tissue engineering.
在这项研究中，我们成功地通过利用 I 型胶原（COL I）和柠檬酸（CA），通过双模板诱导仿生矿化方法制备了镁（Mg）取代的羟基磷灰石纳米复合材料（Mg-HA）。随后，将所得复合纳米颗粒与壳聚糖（CHI）和明胶（Gel）混合，通过三维（3D）打印技术制备具有互连结构的多孔支架。对 Mg-HA 粉末和复合支架进行了表征。结果表明，Mg 取代 Ca 离子降低了 HA 晶体的结晶度，但对纳米复合材料的大小和结构没有显著影响。与具有 Mg 取代的 HA 支架相比，Mg-HA 支架的形态变得更加光滑。此外，通过金属离子释放、细胞附着、增殖和 MC3T3-E1 细胞分化评估了 Mg-HA 复合支架的生物相容性。结果表明，随着更多的 Ca 被 Mg 取代，从样品中释放出更多的 Mg，培养基中的 pH 值变得更酸性。表明 Mg-HA 支架具有更高的细胞附着、增殖率，增加碱性磷酸酶（ALP）活性和骨形成相关基因，包括骨钙素（OCN）、 runt 相关转录因子 2（RUNX2）和 COL I 的表达。因此，表明具有优异生物相容性和生物活性的 3D 打印 Mg-HA 复合支架是骨组织工程的潜在候选材料。
