气相色谱-质谱法同时测定菠菜中4种二缩甲酰亚胺类杀菌剂的残留量

Simultaneous GC Determination of Residual Amounts of 4 Diformylimide Bactericides in Spinach

提出了气相色谱-质谱法同时测定菠菜中乙烯菌核利、乙菌利、腐霉利和异菌脲等4种二缩甲酰亚胺类杀菌剂残留量的方法。样品用丙酮-正己烷(1+4)混合溶剂提取,所得提取液用凝胶色谱进行净化。采用气相色谱分离后,选择离子监测模式下质谱法进行测定。乙烯菌核利、乙菌利、腐霉利和异菌脲的检出限(3S/N)分别为0.01,0.01,0.01,0.02mg·kg^(-1)。取菠菜空白样品在3个浓度水平上加入4种杀菌剂混合标准溶液后,按试验方法进行测定,所得回收率在78.1%～94.9%之间,相对标准偏差(n=6)在4.9%～12%之间。

A method for determination of residual amounts of 4 diformylimide bactericides,i.e.vinclozolin, chlorzolinate,procymidone and iprodione,in spinach by GC-MS was proposed.Samples were extracted with mixed solvent of ethyl acetate and n-hexane（1＋4）.The extract obtained was purified by gel permeation chromatography, and the eluates were taken for separation by GC and the contents of the 4 bactericides were determined by MS under select ion monitoring（SIM） mode.Values of detection limit（3S/N） found were 0.01 mg·kg^（-1） for vinclozolin, 0.01 mg·kg^（-1） for chlorzolinate.0.01 mg·kg^（-1） for procymidone.and 0.02 mg·kg^（-1） for iprodione.Tests for recovery were made by addition of mixed standards to a blank spinach sample at 3 different concentration levels,values of recovery found were in the range of 78.1%-94.9%,with values of RSD＇s（n=6） in the range of 4.9%-12%.