下游处理对PLGA微球分离制备的影响

Influence of different downstream processes on separation of PLGA microparticles

为获得球形度较高且表面光滑的PLGA微球,提高微球的生物相容性,考察了直接冷冻干燥法等不同的下游处理过程对微球分离制备的影响,采用扫描电镜和原子力显微镜对产品进行分析.研究表明:直接冷冻干燥法(一步法)可获得镶嵌有微球的纤维状网络结构,是一种构建与微粒结合有关的组织工程支架材料的新方法;过滤法采用的时间长,不利于酶等物质活性的保持,同时也不易除去PVA;离心处理方法对获取球形度较高且表面光滑的PLGA微球更为有效,而超声分散对微球的形态结构造成影响.

To obtain spherical and smooth PLGA microparticles, and thus to improve the properties such as biocompatibility, SEM and AFM were used to investigate the influence of different downstream proeesses on the morphological properties of PLGA microparticles. Results show that the direct vacuum freeze-drying method （one-step method） can prepare the microparticle-dotted fibriform network, which is a new method in constructing some microparticle-combined polymer based scaffolds. The filtration method wastes much time and is difficult to remove PVA. Besides, long time treatment leads to the loss of added drug. The centrifugation method is more efficacious to obtain spherical and smooth microparticles. Using ultrasonic to separate the aggregates will affect the morphology of microparticles.