利福昔明片的高效液相色谱分析

Determination of Rafaximin and Impurities in Rafaximin Tablets by HPLC

目的 建立利福昔明片中利福昔明及杂质的测定方法。方法 采用高效液相色谱法。色谱柱 :KromasilC18柱(15 0mm× 4 6mm ,5 μm) ;流动相 :甲醇 乙腈 0 0 75mol/L磷酸二氢钾 1 0mol/L枸椽酸 (30∶30∶2 5∶4 ) ;检测波长为 2 36nm。采用外标法测定含量。结果 本色谱条件下利福昔明、中间体、杂质间均能很好的分离 ,空白辅料不干扰主峰 ,利福昔明在 2 0 8～ 2 0 8 2 μg/ml的浓度范围内 ,峰面积与进样量呈良好的线性关系 (r =0 9998) ,最低检测限为 1 95 2 μg ,含量测定的回收率为98 6～ 10 0 5 % ,RSD <1 2 %。结论 该方法专属性强 ,操作方便 ,结果准确 ,重现性好。

Objective To establish a method for the determination of rafaximin in rafaximin tablets by HPLC. Methods Reversed phase chromatographic separation was carried out on a Kromasil C 18 column (150 mm×4 6 mm,5 μm)equilibrated with an eluent mixture constituted by CH 3 OH CH 3CN 0 075 mol·L -1 KH 2 PO 4 1 0 mol·L -1 citic acid (30∶30∶25∶4). The ultraviolet detection was at 236 nm. The quantitative determination of rafaximin was performed with external standard method and the impurity limitation was performed with area normalization method. Results Complete separation was achieved among rafaximin, its intermediates and impurities under optimum conditions. No interference from tablet excipient was found. The standard curve was linear over the concentration range of 2 08 to 208 2 μg·ml -1 for rafaximin and the limit of quantification was 1 952 μg. The recovery of rafaximin was in the range of 98 65% to 100 5% with RSD less than 1 2%. Conclusion The separation method is accurate, reproducible and highly selective.