核-壳结构硅灰石/磷酸钙多孔陶瓷微球的制备及表征

Preparation and Characterization of Core-shell-structured Wollastonite/Calcium Phosphate Porous Bioceramic Spheres

本文研究了双壳层型核-壳结构β-硅灰石/β-磷酸三钙(β-CaSiO3/β-TCP)生物活性复相陶瓷微球的制备及表征;利用添加有机微球造孔剂工艺,在内、外壳层分别构建出孔径10μm左右的多孔结构,并对其体外降解行为进行了分析。结果显示,运用自制同轴喷头微流控系统制备的生物活性复相陶瓷微球的工艺简单,微球尺寸均一,球形形态良好,经干燥、煅烧处理后陶瓷微球发生明显收缩,颗粒度维持在2.2±0.1mm。通过改变组分分布、烧结温度制度以及双壳层内部结构等实现复相陶瓷体外降解的可调节性。以上研究结果表明,该方法制备的多孔双壳层型核-壳结构复相陶瓷微球解决了组分降解速率调控问题,以及由此堆砌颗粒形成三维网络孔道演化可调可控性能,势必将在研究骨缺损修复和微球载药领域具有重要意义。

The regeneration and repair of pathological bone defect is still a great challenge in clinic.Here we demonstrated how a versatile andexible one-step process can generate multilayer bioceramic microspheres with tunable core or shell composition and shell microstructures.The sphere-forming equipment,as a laboratory scale apparatus,is composed of multi-channel injection pump,coaxially aligned multilayer capillaries,and collection container,to help with the formation of bioceramic microspheres beyond homogenous hybrid.We chose β-tricalcium phosphate（CaP）andβ-phase wollastonite（CaSi）to demonstrate the effectiveness of this method in fabricating the bioceramic microspheres with the tunableness mentioned above.The choosing was based on that these materials exhibit excellent bioactivity,and show either slower or faster biodegradation rate than the new bone regeneration rate in vivo.When organic microbeads（～15μm）are premixed into the shell bioceramic slurry,the tailorable porous structures can be introduced into different shell layers after sintering,and thus the permeability is potentially maximized for rapid exchange of guest molecules into and inorganic ions out of the microspheres.This new strategy can be used to fabricate a variety of multilayer porous bioceramic microspheres for applications in tissue engineering and drug delivery,ect..