谷物中草毒死及草净津残留的高效液相色谱-串联质谱法同时测定

Simultaneous Determination of Allidochlor and Cyanazine in Grains by HPLC-ESI MS/MS

采用高效液相色谱-电喷雾电离-串联质谱（HPLC—ESIMS／MS）建立了同时测定谷物中草毒死、草净津残留量的分析方法。样品经二氯甲烷提取，OasisHLB固相萃取柱净化，采用C18色谱柱（250mm×4．6mmi．d．，5μm）分离，甲醇-0．1％甲酸溶液（体积比50：50）洗脱，ESIMS／MS进行测定。草毒死、草净津的线性范围分别为0．02～10．0、0．01～10．0mg／kg，相关系数分别为0．9996、0．9993，检出限分别为0．01、0．005mg／kg，平均加标回收率为80％-102％。

A high performance liquid chromatography- electrospray ionization mass spectrometric （ HPLC - ESI MS/MS） method was developed for the simultaneous determination of allidochlor and eyanazine in grain samples. Two herbicides were extracted from grains with dichloromethane, cleaned up on an Oasis HLB solid-phase extraction（SPE） column, separated on a C 18 column （250×4.6mmi.d.,5μm） using methanol- 0. 1% formic acid （50 ： 50, by volume） solution as mobile phase at a flow rate of 1.0 mL/min, and then determined by ESI MS/MS. The method showed good ]inearities over the concentration range of 0.02 - 10. 0 mg/kg for allidoehlor with a correlation coefficient of 0. 999 6 and 0.01 - 10. 0 mg/kg for cyanazine with a correlation coefficient of 0. 999 3. The detection limits for allidochlor and cyanazine were 0. 01 mg/kg and 0. 005 mg/kg, respectively. The average recoveries of two herbicides in spiked samples were between 80% and 102% .