镁离子作为生物活性离子在骨植入材料中的应用

Application of Magnesium Ions as Bioactive Factors in Orthopedic Implant Materials

生物材料应用于骨组织的修复是目前一个非常热门的研究领域。通过在生物材料中引入促进骨修复的因子(金属离子、药物、生长因子等)来增强生物材料促进骨修复与再生的性能具有非常好的发展前景。大量的研究证实了镁离子可以参加体内许多的生物化学反应,特别是对成骨细胞的增殖以及分化能力具有较为良好的促进作用。镁金属作为骨植入材料,在体内环境中降解可以释放镁离子,从而促进受损骨组织的修复。但是过快的降解速率一直是限制镁金属作为骨植入材料在临床上广泛应用的主要问题,目前尚无理想的技术方案使镁金属的降解在整个骨组织修复周期中保持适宜的降解速率。为了发挥镁离子作为生物活性因子在骨组织修复与再生过程中的作用,近年来越来越多的研究者开始聚焦于如何将镁离子引入传统骨植入材料中,借助镁离子赋予材料促成骨方面的生物活性,例如有的是表面涂层里引入镁离子,有的是在材料基体里面引入镁离子(合金化、化学掺杂、物理混合等),有的是通过搭载在水凝胶里面引入镁离子,有的是把较小的镁金属植入体(如镁钉)作为整个植入系统的一部分等,大量的体内外试验验证了镁的引入对提高骨植入材料的促成骨方面生物活性作用显著。本文首次从镁离子作为促成骨生物活性离子的角度,对通过不同方式把镁离子引入至骨植入材料实现其生物功能化的相关研究进行较为全面的综述,重点关注镁离子的不同引入方式以及促进受损骨组织修复的效果。

The application of biomaterials in bone tissue repair has become a popular research field at present.It has a promising prospect to promote bone repair and regeneration by introducing factors(metal ions,drugs,growth factors,etc.).Many studies have confirmed that magnesium ions can participate in many biochemical reactions in vivo,especially in promoting the proliferation and differentiation of osteoblasts.Magnesium,as bone implant material,degrades and releases magnesium ions in the body environment,thus promoting the repair of damaged bone tissue.However,the rapid degradation rate has always been the main problem limiting the wide application of magnesium as bone implant material in clinical.At present,there is no ideal method to maintain the appropriate degradation rate of magnesium in the whole cycle of bone tissue repair.Recent years,more and more researchers began to focus on how to introduce magnesium ions in traditional bone implant material,with the aid of magnesium ions endowing biomaterial with osteogenic biological activity.For example,some studies introduce magnesium ions into the surface coating and into the material matrix(alloying,chemical doping,physical mixing,etc.),others incorporated magnesium ions into hydrogels or incorporated smaller magnesium implants(such as magnesium nails)as part of the entire implant system.A large number of in vivo and in vitro trials have confirmed that the introduction of magnesium has a significant effect on improving the osteogenic bioactivity of bone implant materials.In this paper,we comprehensively review the different ways of using magnesium ions to achieve biofunctionalization of bone implant materials,focusing on the different ways of introducing magnesium ions and the effect of promoting the repair of damaged bone tissue.