甲硝唑生物粘附微球的体外释药及其粘附性

目的研制具有良好粘附性能和缓释效果的甲硝唑生物粘附微球(Metro-EC-CP微球)。方法通过液中干燥法制备Metro-EC-CP微球。对微球理化性质、体外释药及在SD大鼠体内胃粘膜上的粘附性进行了研究。结果 微球的平均粒径为559.87 μm。体外释药符合一级动力学。微球的释药速率随着粒径的增加及载药量的减少而减慢。Metro-EC-CP微球中粘附性材料CP含量增加,其生物粘附性能增加,而其缓释效果降低。结论乙基纤维素(EC)-卡波姆934P(CP)为17∶3、载药量为25%的微球在动物体内具有良好的胃粘膜粘附性能,药物缓释达8 h。

IN VITRO DRUG RELEASE PROFILES AND MUCOADHESIVE PROPERTY OF BIOADHESIVE MICROSPHERES OF METRONIDAZOLE

AIM: To prepare bioadhesive microspheres of metronidazole (Metro) with prolonging resident time in the stomach and sustaining drug release. METHODS: The microspheres were prepared by a drying-in-liquid method. The appearance, particle size and drug release in vitro were examined. The factors influencing bioadhesive property and drug release, such as ethyl cellulose (EC)/carbopol 934P (CP) ratio, particle size and Metro content were investigated. RESULTS: The average diameter of the Metro-EC-CP microspheres was 559.9 microns. The release profiles of metronidazole were shown to fit to first-order equations well. With the increase of CP content in the Metro-EC-CP microspheres, the microspheres showed better mucoadhesion and faster drug release. The drug release rate decreased with the increase of particle size and the decrease of Metro content. CONCLUSION: The Metro-EC-CP microspheres have a sound mucoadhsive property and sustained drug release when the ratio of EC and CP was 17:3 and Metro content was 25%. The drug release was shown to last for 8 h in 0.1 mol.L-1 hydrochloric acid.