Yuan Junjie, Wang Baoxin, Han Chen, Huang Xiaoyan, Xiao Haijun, Lu Xiao, Lu Jianxi, Zhang Dong, Xue Feng, Xie Youzhuan
Department of Orthopedics, Shanghai Fengxian District Central Hospital, Shanghai Jiao Tong University Affiliated Sixth People's Hospital South Campus, Shanghai 201499, PR China.
Department of Otolaryngology, Head and Neck Surgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201620, PR China.
Mater Sci Eng C Mater Biol Appl. 2020 Sep;114:111037. doi: 10.1016/j.msec.2020.111037. Epub 2020 Apr 30.
The treatment of infectious or potentially infective bone defects remains a major problem in clinical practice. Silver has the ability to potentiate antibiotics against resistant bacterial strains. In order to reduce the risk of long-term infections, it is necessary for the biomaterial scaffold to release Ag in a controlled manner during the entire healing process. In this study, given the antimicrobial characteristics of nanosized Ag (NSAg), we synthesized β-tricalcium phosphate (β-TCP) doped with 5 and 10 wt% NSAg (5 wt% NSAgTCP and 10 wt% NSAgTCP, respectively). The NSAgTCP composites exhibited similar macroporous structures to pure β-TCP. The NSAgTCP samples were examined by scanning electron microscopy at 10,000-times magnification, which revealed that silver was still present at the nanometer scale. X-ray diffraction revealed that silver does not change the crystalline properties of β-TCP. In addition, we observed that the mechanical strength of NSAgTCP increased with increasing amounts of added Ag. The antibacterial, physical, and chemical properties of NSAgTCP were investigated in vitro. We found that NSAgTCP is effective at inhibiting the growth of Staphylococcus aureus and Escherichia coli and is not cytotoxic to human bone marrow mesenchymal stem cells. Moreover, it does not hinder liver or kidney function when tested in vivo. As the bioceramic degrades, Ag ions are slowly released and new bone is formed. No significant cytotoxic effects were observed even when 10 wt% NSAgTCP was used. NSAgTCP has the ability to simultaneously repair bone defects and act as an anti-infective agent; hence, we expect that this material, with its good bone-repairing and anti-infective properties, will find wide spread use as a novel bone substitute.
感染性或潜在感染性骨缺损的治疗仍是临床实践中的一个主要问题。银具有增强抗生素对耐药菌株作用的能力。为降低长期感染风险，生物材料支架在整个愈合过程中以可控方式释放银是必要的。在本研究中，鉴于纳米银（NSAg）的抗菌特性，我们合成了掺杂5 wt%和10 wt% NSAg的β-磷酸三钙（β-TCP）（分别为5 wt% NSAgTCP和10 wt% NSAgTCP）。NSAgTCP复合材料呈现出与纯β-TCP相似的大孔结构。对NSAgTCP样品进行10000倍放大的扫描电子显微镜检查，结果显示银仍以纳米尺度存在。X射线衍射表明银不会改变β-TCP的晶体特性。此外，我们观察到NSAgTCP的机械强度随银添加量的增加而提高。对NSAgTCP的抗菌、物理和化学性质进行了体外研究。我们发现NSAgTCP能有效抑制金黄色葡萄球菌和大肠杆菌的生长，对人骨髓间充质干细胞无细胞毒性。此外，在体内测试时它不会妨碍肝脏或肾脏功能。随着生物陶瓷降解，银离子缓慢释放，新骨形成。即使使用10 wt% NSAgTCP也未观察到明显的细胞毒性作用。NSAgTCP有能力同时修复骨缺损并作为抗感染剂；因此，我们期望这种具有良好骨修复和抗感染性能的材料将作为一种新型骨替代物得到广泛应用。
