HPLC法测定异福酰胺片中有关物质的含量

目的建立HPLC法测定异福酰胺片中已知杂质醌式利福平、N-氧化利福平、3-甲酰利福霉素SV、利福霉素SV、异烟酸、异烟腙和其他未知杂质的含量。方法采用DiamonsilC18(250 mm×4.6mm,5μm)色谱柱,流动相A为磷酸盐缓冲液(10 mmol.L-1磷酸氢二钠溶液,用磷酸调节pH值至6.8)-乙腈(体积比96∶4),流动相B为磷酸盐缓冲液(10 mmol.L-1磷酸氢二钠溶液,用磷酸调节pH值至6.8)-乙腈(体积比55∶45),梯度洗脱,流速为1.0 mL.min-1,检测波长为238 nm,柱温为30℃。已知杂质和未知杂质均采用外标法计算含量。结果各杂质与利福平、异烟肼和吡嗪酰胺分离度良好,样品中醌式利福平、N-氧化利福平、3-甲酰利福霉素SV、利福霉素SV、异烟酸和异烟腙按外标法以峰面积计算其含量分别小于1.5%、1.0%、0.5%、0.5%、1.0%和0.5%,其他未知杂质峰面积的和小于对照溶液中利福平峰面积的3.0%。结论 HPLC法准确、简便、快速,适于测定异福酰胺片中有关物质的含量。

Determination of related substances in rifampin,isoniazid and pyrazinamide tablets by HPLC

Objective To establish an HPLC method for the determination of rifampicin quinone, rifampicin N-oxide, 3-formylrifamycin SV, rifamycin SV, isonicotinic acid, isoniazone and other unknown impurities in rifampin, isoniazid and pyrazinamide tablets. Methods The HPLC method was performed with the Diamonsil^® C₁₈ column (250 mm×4.6 mm, 5 µm). The mobile phase A was 10 mmol·L^-1 dibasic sodium phosphate buffer(adjusted with phosphoric acid to a pH of 6.8) and acetonitrile(V∶V=96∶4)and the mobile phase B was 10 mmol·L^-1 dibasic sodium phosphate buffer(adjusted with phosphoric acid to a pH of 6.8) and acetonitrile(V∶V =55∶45). Gradient elution was used. The flow rate was 1.0 mL·min^-1. The detection wavelength was set at 238 nm. The column temperature was 30 ℃. Both the known and unknown impurities were determined by external standard method. Results Impurities could be separated well from rifampin, isoniazid and pyrazinamide in tablets. The contents of rifampicin quinone, rifampicin N-oxide, 3-formylrifamycin SV, rifamycin SV, isonicotinic acid, isoniazone and other unknown impurities was not more than 1.5%, 1.0%, 0.5%, 0.5%, 1.0%, 0.5% and 3.0%, respectively. Conclusion The HPLC method is found to be accurate, simple and rapid for the determination of related substances in rifampin, isoniazid and pyrazinamide tablets.