高效液相色谱法测定甲氧苄啶片的含量

Determination of trimethoprim tablets by HPLC

目的建立甲氧苄啶片含量的高效液相色谱（HPLC）测定法。方法采用十八烷基硅烷键合硅胶柱；流动相为乙腈-水．三乙胺：200：799：1（冰醋酸调pH至5．9）；检测波长271nm；流速1．0ml·min^-1。甲氧苄啶易溶于醋酸，用少量冰醋酸溶解甲氧苄啶，用水稀释后测定含量。结果甲氧苄啶质量浓度在5—70mg·L^-1范围内与峰面积呈良好线性关系，r=0．9999，平均回收率为98．9％，RSD为0．36％（n=6）。结论本法操作简单，结果准确，重现性好，可用于甲氧苄啶片的含量测定。

Aim To establish a method for the content determination of trimethoprim tablets by HPLC. Method HPLC was used with C18 column. The mobile phase was acetonitrile-water-triethylamine（ 200： 799：1 ） （sodium acetic acid solution adjusted pH to 5.9 ）. The detection wavelength was 271 nm,with a flow rate 1.0 ml·min^-1 . Trimethoprim is soluble in acetic acid. A bit of glacical acetic acid was used to dissolve trimethoprim and its content was determined after dilution by water. Results The calibration curve was linear in the range form 5 mg · L^- 1 to 70 mg · L^- 1 for trimethoprim . The average recovery was 98.9% and RSD was 0.36% （ n = 6）. Conclusion This method is simple, reliable and well repeatable. It can be used for the content determination of trimethoprim tablets.