硝苯地平膜控型控释微丸的制备及体外评价

目的研究硝苯地平(NF)膜控型24 h控释微丸的处方与工艺,并考察其体外释放特性。方法采用液相层积、丸芯上药法制备载药速释微丸,以Eudragit RL100、RS100为包衣材料,流化床悬浮包衣法制备膜控型控释微丸,并对影响微丸释放的处方因素进行了考察。通过与市售渗透泵片拜新同的体外释放度的对比研究,探讨硝苯地平膜控型控释微丸的体外释药特征。结果调整Eudragit RL100、RS100的比例、衣层厚度、致孔剂的用量,可以改变药物的释放速率。当Eudragit RL100、RS100的比例为3∶7,包衣增重为6%时,制备的控释微丸体外释药与市售渗透泵片相似(f2=62.8),具有良好的零级释放特性。结论以丸芯上药法,Eudragit RL100、RS100为控释材料制备的NF膜控型控释微丸,具有良好的零级释放特性,结果可为硝苯地平多单元控释制剂的研究开发提供参考。

Preparation and in vitro evaluation of nifedipine controlled-release coated pellets

Objective To study the preparation and in vitro release characteristics of nifedipine controlled-release coated pellets（NF-CRP）. Methods Rapid-release nifedipine pellets were prepared by liquid layering technology. To control the release, the drug containing pellets were coated with Eudragit RL100 and RS100 as the controlled layer with fl uid bed equipment. The effect of the formulation on drug release was evaluated. The in vitro release behaviors were investigated by comparing with Adalat GITS as the reference. Results The ratio of Eudragit RL100 and RS100, the thickness of the fi lm and the amount of soluble additives infl uenced the drug release behaviors. NF-CRP showed similar in vitro release behaviors with Adalat GITS（f2=62.8） at the ratio of RL100 to RS100 3∶7, increasing coating weight of 6%, and the drug release behaviors followed the zero-order model.Conclusion NF-CRP prepared by fl uidized bed with Eudragit RL100 and RS100 as the controlled release material shows an excellent zero-order release profi le. The study provides a reference for the development of nifedipine controlled release multiple unit dosage.