顶空毛细管GC法测定盐酸苯海拉明原料药中乙醇、甲苯的残留量

Determination of Ethanol and Toluene Residual Solvent in Diphenhydramine Hydrochloride Raw Materia by Headspace Capillary Gas Chromatography

目的：建立测定盐酸苯海拉明原料药中乙醇、甲苯残留量的方法。方法：采用顶空毛细管气相色谱法，以丁酮为内标。色谱柱为Agilent DB-624弹性石英毛细管柱，进样口温度为200℃，氢火焰离子化检测器温度为250℃，载气为高纯氮气，流速为3.0 ml/min，柱温为程序升温，进样方式为分流进样，分流比为20∶1，顶空平衡温度为80℃，平衡时间为30 min，进样时间为1 min。结果：在该色谱条件下，乙醇、甲苯与内标峰能得到良好分离；乙醇、甲苯的检测质量浓度线性范围均为0.02～0.8 mg/ml（r＝0.9998、0.9994）；精密度、稳定性、重复性试验的RSD＜3％，乙醇、甲苯的加样回收率分别为95.50％～103.50％、96.91％～103.74％，RSD分别为2.6％、2.2％（n＝9）。结论：该方法简单、灵敏、准确，可用于盐酸苯海拉明原料药中乙醇、甲苯残留量的测定。

OBJECTIVE：To establish a method for the determination of residual solvent of ethanol and toluene in diphenhydr-amine hydrochloride raw material. METHODS：Headspace capillary gas charmatography and butanone as internal standard were used. The column was Agilent DB-624 capillary column,inlet temperature was 200 ℃,hydrogen flame ionization detector was 250 ℃,the carried gas was high purity nitrogen,flow rate was 3.0 ml/min with temperature programmed,the splitting-ratio was 20∶1,the containers of headspace injector were in equilibrium at 80 ℃ for 30 min,and the injection time was 1 min. RESULTS：With this chromatographic condition,ethanol,toluene and internal standard peak were well separated;there was a good linear rela-tionship of ethanol and toluene in the range of 0.02-0.8 mg/ml （r=0.999 8 and r=0.999 4）;RSDs of precision and stability test were lower than 3%;recoveries were 95.50%-103.50%（RSD=2.6%,n=9） and 96.91%-103.74%（RSD=2.2%,n=9）. CON-CLUSIONS：The method is simple,sensitive and accurate,and can be used for the determination of residual solvent of ethanol and toluene in diphenhydramine hydrochloride raw material.