建立了气相色谱-串联质谱法测定苯甲酸阿格列汀关键起始物料2-氰基溴苄中基因毒性杂质3-氰基溴苄和4-氰基溴苄含量的分析方法。采用50%苯基-50%二甲基聚硅氧烷为固定液的VF-17MS毛细管柱（30 m×0.25 mm，0.25 μm）进行程序升温；进样口温度260℃；以多反应监测（MRM）模式检测。2种待测物均具有较好的线性关系，相关系数均大于0.998 0；检出限（3S/N）均为2.0 μg·L^-1；3-氰基溴苄的回收率为92.1%~97.0%；4-氰基溴苄的回收率为102%~109%；供试品溶液、杂质对照品溶液和系统适用性溶液在室温（25℃）下放置18 h内稳定。三批生产规模样品中均未检出3-氰基溴苄和4-氰基溴苄。建立的分析方法灵敏度高、分离度好、结果准确，可有效分离并测定2-氰基溴苄中的3-氰基溴苄和4-氰基溴苄含量，为苯甲酸阿格列汀的安全性提供了保障。

An analytical method of GC-MS/MS was established for the simultaneous determination of 3-cyanobenzyl bromide and 4-cyanobenzyl bromide in 2-cyanobenzyl bromide used in aglitine benzoate. The method was performed on a VF-17MS capillary column (50% benzene-50% dimethylsiloxane copolymer, 30 m×0.25 mm, 0.25 μm). The column temperature was risen by program. The injector temperature was controlled at 260℃. The analytes were detected with MS/MS in multiple reaction monitoring (MRM) mode. The method was found to show good linearity with regression coefficients all more than 0.998 0. The limits of detection (3S/N) all were 2.0 μg·L^-1. The recoveries of 3-cyanobenzyl bromide were 92.1%-97.0%. And the recoveries of 4-cyanobenzyl bromide were 102%-109%. The test solution, reference solution and system suitability solution were stable for at least 18 h at 25℃. No 3-cyanobenzyl bromide and 4-cyanobenzyl bromide were detected in three batches of production scale samples. With high sensitivity, good resolution and accuracy, the method could be reliably and effectively used in the determination of the above two kinds of trace impurities in 2-cyanobenzyl bromide. This method provides a guarantee for the safety of alogliptin benzoate.