喷雾干燥可控制备生物玻璃微球及其体外生物活性研究

CaO-SiO₂-P₂O₅体系生物玻璃(Bioglass, BG)微球具有良好的生物活性和骨传导性, 在骨组织修复领域得到广泛研究与应用。传统熔融法制备BG粉体的能耗大、粉体形貌不可控、生物活性相对较低; 溶胶-凝胶法制备BG粉体则需大量溶剂、制备周期长、不易量产。为快速、规模化制备形貌、粒径、化学组成可控的BG微球, 本研究以水溶液为溶剂, 以正硅酸四乙酯、磷酸三乙酯、四水硝酸钙为原料, 采用喷雾干燥前驱体溶液方法制备BG微球, 探讨喷雾干燥过程中进气风量、前驱体溶液浓度和进料速率等工艺参数对BG微球粒径的影响; 前驱体溶液化学组成对BG微球的体外诱导磷灰石沉积能力的影响。结果表明, BG微球的粒径范围在40 μm以下可控, 且粒径随前驱体溶液浓度增大而增大, 随进气风量增大而减小, 进料速率则对微球粒径影响较小。不同化学组成的BG微球都具有良好的体外诱导磷灰石沉积能力, 而且随CaO含量的增加而提高。

Controllable Preparation and in Vitro Bioactivity of Bioglass Microspheres via Spray Drying Method

The CaO-SiO₂-P₂O₅ bioglass (BG) microspheres with good bioactivity and osteoconductivity have been extensively studied for bone tissue engineering. Traditional melting method for preparing BG powders is high energy consumption, and difficult to control the morphology of BG. While Sol-Gel technique for BG preparation requires a large amount of organic solvent, long preparation period and low mass production. For the rapid and scalable preparation of BG microspheres with controllable morphology, particle size and chemical composition, an efficient strategy of spray drying of precursor solution was proposed in this study, and the effects of process parameters including inlet air volume, precursor solution concentration and feed rate on the particle size of BG microspheres, and the effect of chemical composition on the apatite formation ability of BG microspheres in vitro were investigated. The results showed that the particle sizes of BG microspheres via spray drying could be controlled below 40 μm, and the particle sizes of BG microspheres increased with the concentration of precursor solution, and decreased with the increase of inlet air volume, but the feed rate has a slight effect on the particle size of the microspheres. On the other hand, BG microspheres with different chemical compositions had good ability to induce apatite formation in vitro, and it increased with the increase of CaO content. Therefore, spray drying method would be promising for rapid and scalable preparation of BG microspheres.