目的 采用气相色谱-电子捕获检测器（GC-ECD）法测定奥美沙坦酯原料药中基因毒性杂质碘甲烷。方法 采用Agilent DB-624毛细管色谱柱（30 m×0.32 mm×1.8 μm），初始柱温40℃，保持5 min，以20℃/min升至200℃，保持2 min，进样口温度160℃，检测器温度300℃，载气为N₂，体积流量为1.5 mL/min，分流比10：1，进样量1 μL。结果 碘甲烷在0.03~0.60 μg/mL线性关系良好；检测限为2.0 ng/mL，定量限为6.0 ng/mL；平均回收率为98.0%，RSD值为1.8%。结论 该方法专属性强、准确性高、灵敏度高、耐用性好，可用于奥美沙坦酯中基因毒性杂质碘甲烷的测定。

Objective To determine the genotoxic impurity methyl iodide in olmesartan medoxomil API by GC-ECD method. Methods The genotoxic impurity was detected on a Agilent DB-624 capillary column (30 m×0.32 mm×1.8 μm). The column temperature was programmed:the initial temperature was 40℃ and was maintained for 5 min. Then the temperature was raised to 200℃ at a rate of 20℃/min and maintained for 2 min. The inlet temperature was 160℃, and electron capture detector temperature was 300℃. N₂ was used as the carrier gas, and the flow rate was 1.5 mL/min, the split ratio was 10:1, the injection volume was 1 μL. Results At the range of 0.03-0.60 μg/mL, the regression equation of methyl iodide was good. The LOD concentration was 2.0 ng/mL, and the LOQ concentration was 6.0 ng/mL. The average recovery rate was 98.0% with the RSD value was 1.8%. Conclusion This method is high specificity, accuracy, sensitivity, and well durability, which can be used for the detection of the genotoxic impurity methyl iodide in olmesartan medoxomil API.

R927.2