西咪替丁原料药中有机溶剂残留量的测定

目的:建立顶空气相色谱法测定西咪替丁原料药中环己烷、丙酮、甲醇、乙醇4种溶剂残留量的方法。方法:色谱柱为键合聚乙二醇毛细管柱;载气为氮气,程序升温;进样口温度为150℃,检测器温度为220℃;分流比为1∶1;流速为5.0mL·min-1;顶空进样,以外标法计算残留溶剂含量。结果:环己烷、丙酮、甲醇、乙醇的检测浓度线性范围分别为0.1488～2.381、0.1826～3.287、0.1496～2.693、0.1448～2.317mg·mL-1,最低检测限分别为0.05～1.2μg;平均回收率在99%以上(RSD≤1.0%,n=5)。结论:该方法灵敏、可靠,重复性好,结果准确,可用于西咪替丁原料药中有机溶剂残留量的测定。

Content Determination of Residual Organic Solvents in Cimetidine

OBJECTIVE： To establish headspace GC method for content determination of residual solvents in cimetidine, such as cyclohexane, acetone, methanol and ethanol. METHODS： An INNOWAX capillary chromatographic column was adopted. The carrier gas was nitrogen and the flow rate was 5.0 mL·min-1. The separation was operated with temperature program. The injection temperature was 150 ℃. The detector temperature was 220 ℃ and the split ratio was 1 ∶ 1. The amount of residual solvents was calculated using external standard method. RESULTS： The linear ranges of cyclohexane, acetone, methanol and ethanol were 0.148 8～ 2.381 mg·mL-1, 0.182 6～3.287 mg·mL-1, 0.149 6～2.693 mg·mL-1 and 0.144 8～2.317 mg·mL-1, respectively. The detection limits were 0.05～1.2 μg. The average recoveries were more than 99% （RSD≤1.0%,n=5）. CONCLUSION： The method is sensitive, accurate, repeatable and reliable for content determination of residual organic solvents in cimetidine.