气相色谱串联质谱-内标法测定大米中杀虫环的含量

Determination of thiocyclam in rice by gas chromatography tandem mass spectrometry-internal standard method

中文关键词:  大米  杀虫环  气相色谱串联质谱仪  内标

英文关键词:rice  thiocyclam  gas chromatography tandem mass spectrometry  internal standard

中文摘要:

      目的 优化气相色谱串联质谱-内标法测定大米中杀虫环残留量。方法 在甲酸酸性条件下, 大米中杀虫环经甲醇提取浓缩后, 通过N-丙基乙二胺(primary secondary amine, PSA)固相萃取小柱净化, 用甲醇-二氯甲烷(1:99, V:V)洗脱, 采用SH-Rxi-5Sil MS毛细管色谱柱分离, 正离子模式电离, 多反应监测(multiple reaction monitoring, MRM), 内标法定量。结果 杀虫环在0.05~1.00 μg/mL范围内线性关系良好(r=0.9995), 在0.10、0.20和0.80 μg 3个浓度水平的平均加标回收率为91.0%~102.1%, 相对标准偏差(relative standard deviation, RSD)在0.78%~3.63%之间。结论 该方法操作简便, 耗时较短, 灵敏度高, 重现性好, 适用于大米中杀虫环残留的定性和定量测定。

英文摘要:

      Objective To optimize the gas chromatography tandem mass spectrometry-internal standard method for the determination of thiocyclam in rice. Method Under formic acid acidic conditions, thiocyclam in rice was extracted by methanol, purified by primary secondary amine(PSA) solid-phase extraction column, and eluted with methanol dichloromethane (1:99, V:V). Thiocyclam was separated by SH-Rxi-5Sil MS capillary gas chromatographic column, with electron ion source in positive mode and multiple reaction monitoring (MRM), and quantified by inner standard solution. Results Thiocyclam showed a good linear relationship in the range from 0.05 to 1.00 μg/mL, and the correlation coefficient was 0.9995. The recoveries at 3 spiked levels (0.10, 0.20 and 0.80 μg) were 91.0%~102.1%, with the relative standard deviations (RSD) of 0.78%~3.63%. Conclusion This method is simple, convenient, sensitive and reproducible, which is suitable for the qualitative and quantitative determination of thiocyclam in rice.