反溶剂重结晶法制备阿奇霉素超细粉体

采用反溶剂重结晶法进行了阿奇霉素微粉化实验研究。系统考察了药物溶液质量浓度、溶剂反溶剂比例、搅拌时间、干燥方式等因素对产品形貌和粒度的影响。得到较优的制备工艺条件为：药物溶液质量浓度0.2 g/mL、溶剂反溶剂体积比1:20及搅拌时间10 min，可制备出平均粒径为 270 nm的药物颗粒，经喷雾干燥可得粒径为2~5 μm的阿奇霉素超细粉体。采用扫描电镜、比表面积测试、红外光谱分析和体外溶出实验对原料药及产品性质进行分析表征，分析结果表明，阿奇霉素超细粉体化学结构不变，且比表面积增大8倍，溶解速率明显提高。

Preparation of ultrafine azithromycin by anti-solvent recrystallization

Ultrafine azithromycin (AZM) powder has been prepared by anti-solvent recrystallization. The effects of varying the experimental parameters, such as AZM solution concentration, solvent/anti-solvent ratio, stirring time and drying method, on the particle size and morphology, were investigated. The results showed that the optimum conditions were an AZM solution concentration of 0.2 g/mL, solvent/anti-solvent ratio of 1:20 and stirring time of 10 min. Under these conditions, ultrafine AZM particles with a mean particle size of 270 nm could be precipitated. AZM dry powder with a particle size ranging from 2 to 5 μm was subsequently prepared by spray drying. The commercial crude AZM and as prepared powder were characterized by SEM, BET, FT-IR and dissolution tests. The analyses indicated that the chemical structure of as-prepared ultrafine AZM powder remained unchanged. The specific surface area of the ultrafine AZM powder increased 8 times and it exhibited a significantly improved dissolution rate.