National Glycoengineering Research Center, Shandong University, Jinan, 250100, People's Republic of China.
J Biomed Mater Res A. 2011 Dec 15;99(4):554-63. doi: 10.1002/jbm.a.33212. Epub 2011 Sep 20.
An injectable and self-setting bone repair materials (nano-hydroxyapatite/collagen/calcium sulfate hemihydrate, nHAC/CSH) was developed in this study. The nano-hydroxyapatite/collagen (nHAC) composite, which is the mineralized fibril by self-assembly of nano-hydrocyapatite and collagen, has the same features as natural bone in both main hierarchical microstructure and composition. It is a bioactive osteoconductor due to its high level of biocompatibility and appropriate degradation rate. However, this material lacks handling characteristics because of its particle or solid-preformed block shape. Herein, calcium sulfate hemihydrate (CSH) was introduced into nHAC to prepare an injectable and self-setting in situ bone repair materials. The morphology of materials was observed using SEM. Most important and interesting of all, calcium sulfate dihydrate (CSD), which is not only the reactant of preparing CSH but also the final solidified product of CSH, was introduced into nHAC as setting accelerator to regulate self-setting properties of injectable nHAC/CSH composite, and thus the self-setting time of nHAC/CSH composite can be regulated from more than 100 min to about 30 min and even less than 20 min by adding various amount of setting accelerator. The compressive properties of bone graft substitute after final setting are similar to those of cancellous bone. CSD as an excellent setting accelerator has no significant effect on the mechanical property and degradability of bone repair materials. In vitro biocompatibility and in vivo histology studies demonstrated that the nHAC/CSH composite could provide more adequate stimulus for cell adhesion and proliferation, embodying favorable cell biocompatibility and a strong ability to accelerate bone formation. It can offer a satisfactory biological environment for growing new bone in the implants and for stimulating bone formation.
本研究开发了一种可注射自固化骨修复材料（纳米羟基磷灰石/胶原/半水硫酸钙，nHAC/CSH）。纳米羟磷灰石/胶原（nHAC）复合材料是由纳米羟磷灰石和胶原自组装而成的矿化纤维，在主要的层次结构和组成方面与天然骨具有相同的特征。由于其高度的生物相容性和适当的降解率，它是一种生物活性的骨传导剂。然而，由于其颗粒或固体预制块的形状，该材料缺乏可处理的特性。在此，将半水硫酸钙（CSH）引入 nHAC 中，制备可注射自固化原位骨修复材料。采用 SEM 观察材料的形态。最重要和有趣的是，半水硫酸钙（CSH）不仅是制备 CSH 的反应物，也是 CSH 的最终固化产物，被引入 nHAC 作为固化促进剂来调节可注射 nHAC/CSH 复合材料的自固化特性，从而使 nHAC/CSH 复合材料的自固化时间可以从 100 多分钟调节到约 30 分钟，甚至少于 20 分钟，只需加入不同量的固化促进剂。最终固化后骨移植替代物的抗压性能与松质骨相似。CSD 作为一种优良的固化促进剂，对骨修复材料的机械性能和降解性没有显著影响。体外生物相容性和体内组织学研究表明，nHAC/CSH 复合材料可以为细胞黏附和增殖提供更充足的刺激，体现出良好的细胞生物相容性和促进骨形成的强大能力。它可以为植入物中新生骨的生长和刺激骨形成提供满意的生物学环境。
