高效液相色谱法测定甲硝唑结肠定位缓释微丸的含量

Determination of metronidazole in colon-specific sustained-release pellets with high performance liquid chromatography

目的建立甲硝唑结肠定位缓释微丸的含量测定方法。方法采用反向高效液相色谱法（HPLC），流动相为甲醇：乙腈：0．05mol／L磷酸二氢钾（用0．01mol／L磷酸溶液调节pH至3．5）（17．5：17．5：65，V／V／V），流速1．0ml／min，柱温25℃，检测波长317nm。结果缓释微丸中的辅料对甲硝唑的测定无干扰。甲硝唑在4～24μg/ml范围内线性关系良好，以甲硝唑浓度（C）对峰面积（A）进行线性回归，标准曲线方程为A=76386C＋36330，r=-0．9999；日内、日间标准偏差均〈2％；平均回收率均98．9％～100．1％。结论该方法的精密度、准确度、重现性均符合中国药典的规定，可用于甲硝唑结肠定位缓释微丸的含量测定及稳定性研究。

Objective To establish a high performance liquid chromatography method for determining metronidazole in colon-specific sustained-release pellets. Methods High performance liquid chromatography （HPLC） method was used with the mobile phase containing methanol：acetonitrile：0.05 mol/L potassium dihydrogen phosphate solution （17.5：17.5：65, V/V/V）. Column temperature was set at 25 ~C. Flow rate of mobile phase was 1.0 ml/min and wavelength of detector was set at 317 nm. Results Excipients in colon-specific sustained-release pellets did not interfere with the determination of metronidazole. The standard curve was linear over metronidazole concentration range of 4.02-24.12 μg/ml. A typical equation of calibration curve was： A=76 386C＋36 330 （r=0.9999）. The RSD of precision was less than 2%, mean recovery was between 98.9%-100.1%. Conclusion The precision, accuracy and re- peatability could meet the requirements of China Pharmacopoeia （2005）. The method can be used for determination of metronidazole in colon-specific sustained-release pellets and investigation of the preparation stability.