硼硅酸盐生物活性玻璃在直流电场下的体外矿化性能

In vitro Mineralization Property of Borosilicate Bioactive Glass under DC Electric Field

硼硅酸盐生物活性玻璃具有良好的生物活性和骨传导性,但大多数生物活性玻璃表现出非线性降解和矿化行为,矿化性能会随着时间而减缓。电场作为一种外场辅助调节的方法,能够干预玻璃的离子交换和扩散。本研究利用直流电场干预硼硅酸盐生物活性玻璃的体外矿化,加快降解较慢阶段中硼硅酸盐生物玻璃的生物活性。将熔融法制备的成分为18SiO_(2)-6Na_(2)O-8K_(2)O-8MgO-22CaO-2P_(2)O_(5)-36B_(2)O_(3)的硼硅酸盐生物活性玻璃浸泡在SBF生理模拟液中,施加0~90 mA的电流,研究直流电场对硼硅酸盐生物玻璃降解及体外矿化性能的影响。研究结果表明,施加电场不仅可以提高硼硅酸盐生物活性玻璃的降解率和离子释放量,而且有利于玻璃网络水解和表面羟基化,加速羟基磷灰石的生成。其中失重率比对照组提高了3%~5%,硼和钙的离子释放量分别较对照组提高了2.3~2.9倍和1.9~2.3倍。对硼硅酸盐生物活性玻璃表面结构分析得出,暴露在电场下的样品表面生成了磷灰石层。应用直流电场可以提高生物活性玻璃的降解及体外矿化性能,为提升骨修复效果提供了一种新思路。

Borosilicate bioactive glass has excellent bioactivity and bone conductivity,but most bioactive glasses exhibit nonlinear degradation and mineralization behavior,with mineralization property declining over time.The direct current(DC)electric field,as an outfield-assisted approach to regulation,can interfere in the ion exchange and diffusion of the glass to modify its property.In this study,a DC electric field is used to intervene in vitro mineralization of borosilicate bioactive glass to accelerate the bioactivity in the slower degradation phase.Borosilicate bioactive glass with the composition of 18SiO_(2)-6Na_(2)O-8K_(2)O-8MgO-22CaO-2P_(2)O_(5)-36B_(2)O_(3),prepared by the melting method,was immersed in simulated body fluid(SBF).A current in range of 0-90 mA was applied to study the effect of DC electric field on the degradation and in vitro mineralization property of borosilicate bioactive glass.The results show that the application of electric field increases the degradation rate and ion release of borosilicate bioactive glass.Compared to the control group(without electric field),the weight loss rate increased by 3%–5%and the dissolution of B and Ca ions increased by 2.3–2.9 and 1.9–2.3 times,respectively.Meanwhile,the electric field assists glass network hydrolysis and surface hydroxylation,accelerating the generation of hydroxyapatite(HA).Analyzing the surface structure of the borosilicate bioactive glass particles,we found that an apatite layer was formed on the surface of the sample exposed to the electric field.Hence,the application of a DC electric field can improve the degradation and in vitro mineralization property of bioactive glass,providing a new idea for bone repair effect enhancement.