Abstract An innovative, moldable and injectable bone substitute material comprised of microspheres of sodium alginate (SA)/TOCNF and β-tricalcium phosphate (β-TCP) as the solid phase and carrier SA as the gel phase was developed. The microspheres were prepared by a droplet extrusion crosslinking technique using an aqueous calcium chloride solution. The purpose of this study was to explore the osteoconductivity of the prepared injectable microspheres by filling critically sized bone defects. The in vitro biocompatibility and cytotoxicity of the microspheres were analyzed in MC3T3-E1 osteoblast-like cells using an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5diphenyltetrazolium bromide) assay. An in vivo investigation in a rabbit model indicated that the prepared SO3T20 microspheres showed significantly better bone formation than the control after two and four weeks of implantation. The outcomes demonstrated that the microspheres delivered support for osteogenic differentiation. These results suggest that this novel injectable bone substitute material may be useful for bone tissue engineering.

中文翻译：

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用于骨再生的新型 TOCNF 增强可注射海藻酸盐/β-磷酸三钙微球

摘要 以海藻酸钠（SA）/TOCNF和β-磷酸三钙（β-TCP）微球为固相，载体SA为凝胶相，开发了一种创新、可模压、可注射的骨替代材料。使用氯化钙水溶液通过液滴挤出交联技术制备微球。本研究的目的是通过填充临界尺寸的骨缺损来探索制备的可注射微球的骨传导性。微球的体外生物相容性和细胞毒性在 MC3T3-E1 成骨细胞样细胞中使用 MTT（3-（4,5-二甲基噻唑-2-基）-2,5-二苯基溴化四唑）测定进行分析。兔模型的体内研究表明，在植入 2 周和 4 周后，制备的 SO3T20 微球显示出明显优于对照的骨形成。结果表明微球为成骨分化提供支持。这些结果表明这种新型可注射骨替代材料可能对骨组织工程有用。