RP-HPLC内标法测定二氯喹啉酸钠盐的含量

Determination of sodium uinclorac with HPLC by using internal standard method

建立了高效液相色谱内标法测定二氯喹啉酸钠盐含量的方法。以邻苯二甲酸二乙酯为内标物，二氯喹啉酸为标样，采用AgilentEclipse XDB—C18（150mrn×4，6mm，5μm），柱温25℃，以甲醇-0．5％磷酸水（V（甲醇）：V（0．5％磷酸水）=60：40）为流动相，流速为1．0mL／min，检测波长为230nm，进样体积10肛L，按内标法以峰面积计算二氯喹啉酸钠盐含量。在该色谱条件下二氯喹啉酸钠盐在21．5～430μg／mL范围内二氯喹啉酸钠盐色谱峰面积与其浓度成良好线性关系，R=0．9999（n=6）；最低定量限为0．2μg／mL（信噪比S／N〉10），检出限0．08μg／mL（信噪比S／N〉3）；平均回收率为103．8％，RSD为1．14％（n=6）。该方法具有准确度高、检测限低、重复性好等优点，适用于二氯喹啉酸钠盐的含量检测。

A HPLC internal standard method with UV detec- tion has been developed for the determination of sodium uin- clorac with diethylphthalate as internal standard and uinclorac as reference substances. The chromatographic separation was obtained on a reversed phase C18 column with the mobile phase of methanol/water mixture of 0. 5% phosphoric acid （60：40,V/V） at a flow rate of 1.0 mL/min. The UV detec- tion wavelength was set at 230 nm and the column tempera- ture was set at 25 ℃ with 10 μL injection volume. The cali- bration curve was good linear in the range of 21.5 ~ 430 μg/mL and the linear correlation coefficient was 0. 999 9 （ n = 6）. The lower limit of quantificantion was 0. 2 μg/mL （S/N 〉 10） and the lowest threshold was 0.08 μg/mL （S/N〉3）. The average of recovery was 100.8% with RSD = 1. 14%. The results showed that this method is accu- rate and precise with lower threshold. Therefore,it is applicable to detect the sodium uinclorac.