Stability indicating RP-HPLC method for simultaneous determination of gatifloxacin and dexamethasone in binary combination

Abstract In this study, conditions were optimized for development of a simple RP-HPLC method for simultaneous analysis of gatifloxacin and dexamethasone in different matrices like pharmaceuticals, human serum and urine. Good separation of gatifloxacin and dexamethasone from the induced degradation products was accomplished using C8 as stationary phase; 0.02 M phosphate buffer (pH 3.0) and methanol (42:58 v/v) as mobile phase. The concentration was measured with DAD at 270 nm. Linearity was observed in the range of 0.000040-0.000280 mol/L for gatifloxacin (r2≥0.999) and 0.000013-0.000091 mol/L for dexamethasone (r2≥0.999). Both the analyte peaks were completely separated from the peaks of induced degradation products as indicated by the peak purity index (≥0.9999 for both analytes). The optimized method is recommended to be used for concurrent analysis of gatifloxacin and dexamethasone in different matrices.

摘要 本研究优化了一种简便的反相高效液相色谱法（RP-HPLC）的实验条件，用于同时分析药物制剂、人血清及尿液等不同基质中的加替沙星（gatifloxacin）与地塞米松（dexamethasone）。该方法采用C8作为固定相，以0.02 mol/L磷酸盐缓冲液（pH 3.0）与甲醇按42:58体积比混合作为流动相，可实现加替沙星、地塞米松与诱导降解产物的良好分离。采用二极管阵列检测器（DAD）在270 nm波长下对两种待测物进行浓度测定。加替沙星的线性范围为0.000040~0.000280 mol/L（决定系数r²≥0.999），地塞米松的线性范围为0.000013~0.000091 mol/L（决定系数r²≥0.999）。峰纯度指数结果显示，两种待测物的色谱峰均与诱导降解产物峰完全分离（两种待测物的峰纯度指数均≥0.9999）。本研究优化得到的方法可推荐用于不同基质中加替沙星与地塞米松的同步分析。