Xiao Qiyao, Zhou Kechao, Chen Chao, Jiang Mingxiang, Zhang Yan, Luo Hang, Zhang Dou
State Key Laboratory of Powder Metallurgy, Central South University, Changsha, Hunan 410083, China.
Department of Mechanical Engineering, University of Bath, Bath BA2 7AY, UK.
Mater Sci Eng C Mater Biol Appl. 2016 Dec 1;69:1068-74. doi: 10.1016/j.msec.2016.07.082. Epub 2016 Aug 2.
Microspheres with hollow and/or porous structures have been widely used in various applications. A new method of spraying and freezing emulsions was developed to prepare hollow HA (hydroxyapatite) microspheres with interconnected pores by using PVA (polyvinyl alcohol) as emulsifiers and binders. The relationships between viscosity and shear time or rates were tested and the dispersing stability of oil in water (O/W) emulsions was characterized with comparison to suspensions without the addition of oil phase. The effects of solid loadings of HA and the volume ratio between oil and water on the morphologies of microspheres were investigated. Hollow HA microspheres with particle diameter of ~20μm and pore size of ~0.6μm were successfully obtained by spray freezing method. Besides, drying and sintering processes were crucial to the formation of hollow and porous structures, respectively. The gentamicin loading and releasing of HA porous microspheres with different hollow volumes were tested.
具有中空和/或多孔结构的微球已被广泛应用于各种领域。开发了一种喷雾冷冻乳液的新方法，以聚乙烯醇（PVA）作为乳化剂和粘合剂，制备具有相互连通孔隙的中空羟基磷灰石（HA）微球。测试了粘度与剪切时间或速率之间的关系，并与未添加油相的悬浮液进行比较，表征了水包油（O/W）乳液的分散稳定性。研究了HA的固含量以及油相和水相的体积比对微球形态的影响。通过喷雾冷冻法成功获得了粒径约为20μm、孔径约为0.6μm的中空HA微球。此外，干燥和烧结过程分别对中空和多孔结构的形成至关重要。测试了不同中空体积的HA多孔微球的庆大霉素负载和释放情况。
