目的 建立GC-MS/MS法测定甲磺酸卡莫司他原料药中的亚硝胺类基因毒性杂质N-亚硝基二甲胺（NDMA）。方法 采用Agilent DB-SELECT 624UI色谱柱（30 m×0.32 mm×1.80 μm）色谱柱，离子源为EI源，采用多反应监测模式，以m/z74→44.2为定量离子，m/z 74→42.2为定性离子，进行数据采集。结果NDMA在12.571 2～100.569 6 ng/mL线性良好（r=0.997 6），检测限质量浓度为5.028 5 ng/mL，平均回收率为107.4%，RSD值为2.5%。结论 该方法操作简单，灵敏度高，专属性和重复性好，可用于甲磺酸卡莫司他原料药中NDMA的检测。

Objective To establish a GC-MS/MS method for determination of genotoxic impurityN-nitrosodimethylamine (NDMA) in camostat mesylate active pharmaceutical ingredients.Methods NDMA was determined by GC-MS/MS method with Agilent DB-SELECT 624UI column (30 m×0.32 mm×1.8 μm). The mass spectrometer was operated in the electron impact ionization (EI) fixed mode, and the ion collection mode was multiple reaction monitoring (MRM). The ion for quantitative wasm/z74 → 44.2, and for qualitative wasm/z 74 → 42.2.Results NDMA had a good linear relationship 12.571 2 — 100.569 6 ng/mL withr = 0.997 6. The limit of detection (LOD) was 5.028 5 ng/mL. The average recovery was 107.4%with RSD value 2.5 %.Conclusion The method is convenient sensitive, specific, and reproducible, which is suitable for determination of NDMA in camostat mesylate active pharmaceutical ingredients.

R927.2