含锶硼酸盐基生物玻璃经晶化处理后对其溶解性能及体外生物活性的影响

通过对含锶硼酸盐基玻璃进行微晶化处理,以考察该玻璃由玻璃态转化为晶态时体外生物活性和降解性的改变。采用熔融法制备不同锶含量(n(SrO)=0、2%、6%)的硼硅酸盐生物玻璃,然后在700℃/4h条件下微晶化处理,分别获得微晶化前后的试样。将各组玻璃及微晶化的样品浸泡在类似于生理模拟液的0.02mol/L的K2HPO4溶液中(以1g玻璃对应100mL浸泡液的比例),置于37℃恒温条件下,进行体外生物矿化反应。用XRD和FT-IR对反应后产物进行表征,并测定不同浸泡时间下样品的质量损失率以及浸泡液的pH值。结果表明,微晶化处理前后的含锶的硼硅酸盐玻璃试样在浸泡实验中都可以转化成含锶羟基磷灰石,即微晶化后的试样仍然具有体外生物活性;并且微晶化后试样的离子溶出速度能够减缓,降低了原玻璃相对骨组织生长来说的较高的降解速度,可以更加匹配骨组织生长的周期。因此,微晶化处理硼硅酸盐玻璃可实现对降解速度的调控,使该微晶化的生物玻璃有可能在骨组织修复中得到临床应用。

Effect of the crystallization treatment of bioactive borate-based glass containing strontium on its degradation and bio-activity in vitro

For the research of the effect of crystallization treatment on bioactivity in vitro and degradability(dissolution) of borate-based glasses containing strontium,particle samples with different strontium content were prepared by a melting process(n(SrO)=0,2%,6%) and then heat-treated at 700℃ for 4h.After immersed in a 0.02mol/L K2HPO4 solution(a similar solution to simulation body fluid solution,SBF) at 37℃ with a given period of time,with the ratio of 1g glass powder corresponding 100mL solution,each group of samples both before and after crystallization were characterized by mass loss analysis,pH value measurement of the solution,and their immersion products were analyzed by X-ray diffraction and FT-IR.The results show that the samples both before and after crystallization can convert into the strontium-contained hydroxylaptite,showing the virtro bioactivity,and that the ion leach rate from the samples can be slow down after crystallization,thus reducing the high degradability rate of the borate-based glasses,that can be matched with the bone growth rate.Therefore,the biodegradability rate of the samples can be adjusted by the crystallization of borate-based glasses and this kind of crystallized glass would be found their clinic application in bone repair.