甲硝唑缓释药的制备与表征

Synthesis and characterization of controlled-release preparation of metronidazole

目的制备甲硝唑缓释药,提高甲硝唑水溶性和缓释效果。方法通过超声法用海藻酸钠包裹甲硝唑,制备甲硝唑缓释药,以红外光谱、核磁氢谱、差式扫描量热分析和扫描电镜表征该缓释药理化结构,根据国标测定其溶解度,并用紫外光分光光度法测定其包合率和缓释效果。结果本实验制得了一种甲硝唑缓释药,通过正交实验确定了最佳反应条件为:物料摩尔比3∶1、反应功率400 W、反应时间200 s。通过红外光谱、核磁氢谱、差式扫描量热分析和扫描电镜分析,确证该包合物为海藻酸钠包裹甲硝唑的产物。该缓释药溶解度可达18.99 mg/ml,体外释放结果表明12 h内甲硝唑的释放量达40%。结论用海藻酸钠包裹甲硝唑,成功制备了具有良好缓释效果的甲硝唑缓释药。

Objective To increase the solubility of metronidazole in water in order to increase its bioavailability. Methods A new controlled-release preparation of metronidazole was synthesized by using sodium alginate which had good solubility in wa-ter, degradation and characteristics of biocompatibility. The chemical structures of the controlled-release preparation were charac- terized by FT-IR, 1H-NMR, DSC and SEM. The solubility was assayed according to the National Standard. The inclusion rate and controlled-release effect were assayed by UV spectrum. Results The inclusion rate could reach maximum under the optimum con-ditions of molar ratio of 3 ： 1, ultrasonic power of 400 W, and reaction time of 200 s. The solubility of the controlled-release prepa-ration in water increased to 18.99 mg/ml. There was 40% metronidazole released in 12 h in buffer solution. Conclusion A new controlled-release preparation of metronidazole is synthesized successfully by using sodium alginate and its release rate is satisfac-tory.