喷雾干燥法制备泼尼松龙微粉

对不同的泼尼松龙体系（包括溶液和混悬液）的喷雾干燥过程进行了考察。实验研究发现：直接喷雾干燥泼尼松龙溶液能够得到平均粒径为1.07μm且粒度分布窄的球形微粉；喷雾干燥羟丙基甲基纤维素（HPMC）溶液能够得到粒径在4?μm左右的囊状颗粒。当喷雾干燥混悬液时，在较低的进口温度下，喷雾干燥只能作为一种干燥手段来干燥混悬液中原有的颗粒，不能改变原有颗粒的形貌；在较高的进口温度下，喷雾干燥可以成为制备粒径在1～5μm的泼尼松龙和HPMC包合物的有效手段。另采用SEM对不同喷雾干燥条件下得到的样品进行分析与表征，对其形成过程进行研究，并对得到的产品在药物速释、控释方面的应用前景进行了探讨。

Preparation of prednisolone micro-powders by spray drying

Several systems for spray drying of prednisolone solution and suspensions have been studied. Spherical prednisolone microparticles with an average particle sizeof 1.07μm and a narrow particle size distribution and sacculated hydoxypropylmethylcellulose (HPMC) particles with mean particle size of about 4μm were obtained by directly spray drying the respective solutions. For suspensions, at low temperatures (slightly higher than the boiling point of water) the spray drying process was used to dry previously formed particles in suspension, while at higher temperatures, an inclusion complex of prednisolone and HPMC with mean particle size of 3.96μm was prepared. The morphology of the different microparticles was studied by scanning electron microscopy (SEM). In addition, the mechanism of the formation process and potential future applications of the materialshave been explored.