Faculty of New Sciences and Technologies, Semnan University, Semnan, Iran.
Department of Biomedical Engineering, Yazd Branch, Islamic Azad University, Yazd, Iran.
IET Nanobiotechnol. 2019 Sep;13(7):720-725. doi: 10.1049/iet-nbt.2019.0125.
Collagen (Col) type I, as the major component of the bone extracellular matrix has been broadly studied for bone tissue engineering. However,inferior mechanical properties limit its usage for load bearing applications. In this research, freeze dried Col scaffolds are coated with graphene oxide (GO) through a covalent bond of the amine Col with the graphene carboxyl groups. The prepared scaffolds were then reduced using a chemical agent. Scanning electron microscopy exhibited a porous structure for the synthesized scaffolds with an approximate pore size of 100-220 ± 12 µm, which is in the suitable range for bone tissue engineering application. Reducing the GO coating improved the compressive modulus of the Col from 250 to 970 kPa. Apatite formation was also indicated by immersing the scaffolds in simulated body fluid after five days. The cytocompatibility of the scaffolds, using human bone marrow-derived mesenchymal stem cells, was confirmed with MTT analysis. Alkaline phosphatase assay revealed that reducing the Col-GO scaffolds can effectively activate the differentiation of hBM-MSCs into osteoblasts after 14 days, even without the addition of an osteogenic differentiation medium. The results of this study highlight that GO and its reduced form have considerable potential as bone substitutes for orthopaedic and dental applications.
胶原蛋白（Col）I 型作为骨细胞外基质的主要成分，已广泛应用于骨组织工程研究。然而，较差的机械性能限制了其在承重应用中的使用。在这项研究中，通过 Col 上的胺基与石墨烯羧基之间的共价键，将冻干的 Col 支架用氧化石墨烯（GO）进行涂层。然后，使用化学试剂还原制备的支架。扫描电子显微镜显示合成支架具有多孔结构，孔径约为 100-220 ± 12 μm，适用于骨组织工程应用。GO 涂层的减少将 Col 的压缩模量从 250 提高到 970 kPa。将支架浸泡在模拟体液中 5 天后，也表明有磷灰石形成。通过 MTT 分析证实了支架对人骨髓间充质干细胞的细胞相容性。碱性磷酸酶测定表明，即使不添加成骨分化培养基，还原后的 Col-GO 支架也能在 14 天内有效促进 hBM-MSCs 向成骨细胞分化。这项研究的结果表明，GO 及其还原形式在骨科和牙科应用中具有作为骨替代物的巨大潜力。
