Enhanced Osseointegration of Zn-Mg Composites by Tuning the Release of Zn Ions with Sacrificial Mg-Rich Anode Design
Enhanced Osseointegration of Zn-Mg Composites by Tuning the Release of Zn Ions with Sacrificial Mg-Rich Anode Design
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通过牺牲富镁阳极设计调节锌离子的释放来增强锌镁复合材料的骨整合
DOI：
10.1021/acsbiomaterials.8b01137
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发表时间：
2019
影响因子：
--
通讯作者：
Zheng Yufeng
中科院分区：
文献类型：
--
作者：
Yang Hongtao;Qu Xinhua;Lin Wenjiao;Chen Dafu;Zhu Donghui;Dai Kerong;Zheng Yufeng
相对较慢的降解速度和过度释放Zn2+离子导致的骨整合延迟是使用纯锌离子生物可吸收骨科植入物的两个主要缺点。鉴于此，我们设计了一种阴极保护策略，将作为牺牲阳极的Mg掺入Zn中形成Zn-Mg复合材料。在体外和体内条件下系统地评估了新型锌镁复合材料的降解行为和生物相容性。与纯 Zn 相比，富 Mg 相（阳极）和 Zn 基体相（阴极）之间形成的宏观电耦合加速了 Zn-Mg 复合材料的降解。成分分析表明，ZnO 是 Zn-Mg 复合材料的主要产物，随后在骨愈合过程中形成钙化基质。细胞毒性测定显示添加镁后细胞活力显着提高。组织学分析表明纯锌组骨整合延迟。相比之下，随着时间的推移，发现新骨和 Zn-5Mg 复合材料之间在多个位置直接接触，并且骨结合面积增加。通过选择性腐蚀牺牲富镁相共同释放 Zn2+ 和 Mg2+ 离子的协同生物效应有助于改善骨整合。因此，引入牺牲富镁阳极是一种有效的设计策略，可以提高纯锌的降解速率，同时提高其骨整合能力。
Relatively slow degradation rate and delayed osseointegration induced by excessive release of Zn2+ions are two main disadvantages of the use of pure Zn ion bioabsorbable orthopedic implants. In light of this, we designed a cathodic protection strategy by incorporating Mg, acting as a sacrificial anode, into Zn to form Zn-Mg composites. The performance of novel Zn-Mg composites with regard to degradation behavior and biocompatibility was evaluated systematically underin vitroandin vivoconditions. Macro-galvanic coupling that formed between the Mg-rich phase (anode) and the Zn matrix phase (cathode) accelerated the degradation of Zn-Mg composites as compared to that of pure Zn. Composition analysis revealed ZnO as the dominant product of Zn-Mg composites, followed by calcification matrix formation during the bone healing process. Cytotoxicity assay showed prominently improved cell viability after addition of Mg. Histological analysis manifested delayed osseointegration for the pure Zn group. In contrast, direct contact between new bone and Zn-5Mg composite in multiple locations and increased bone bonding areas were found over time. The synergic biological effect of co-releasing Zn2+and Mg2+ions by preferential corrosion of sacrificial Mg-rich phase contributed to the ameliorated bone integration. Thus, introducing sacrificial Mg-rich anode is an effective design strategy to increase the degradation rate of pure Zn while simultaneously improving its bone integration ability.