固相微萃取结合气质联用测定血浆中敌草快

目的采用固相微萃取结合气相色谱-质谱联用方法快速测定血浆中的敌草快含量。方法采用硼氢化钠/氯化镍还原反应和顶空固相微萃取处理样本,气质联用检测方法,以乙基百草枯为内标,检测血浆中敌草快的含量,对还原反应和萃取的温度、时间等实验条件进行优化,并对方法学进行评价。结果采用m/z 194作为定性定量离子,在0.1~50μg/mL浓度范围内线性关系良好（Y=0.076 9X＋0.274 8,r2=0.997 5）,日内和日间精密度分别小于3.99%、5.64%。回收率为92.59%~101.27%,最低定量限为50ng/mL。敌草快还原产物1,1’-乙基-2,2’-联哌啶存在顺式和反式两种同分异构体,两者比率为1∶5.3,相对标准偏差为13.1%（n=17）。结论本文方法准确、快速、重现性好,可以在血浆等生物样品敌草快含量测定中选用。

Fast determination of diquat in plasma samples by solid phase microextraction combined with GC / MS

Objective We developed a method by GC/MS and headspace solid-phase microextraction （HS-SPME） for rapid determination of diquat in plasma samples. Methods The method involved the procedures of sodium borohydride-nickel chloride（NaBH4-NiCl2） reduction and HS-SPME. Ethyl-paraquat was used as internal standard. GC/MS was used to identify and quantify the analytes. The parameters that affected the reduction and extraction were also investigated, and the methodology was evaluated. Results In the range of 0. 1 -50 Ixg/mL, good linearity （Y = 0. 076 9X ＋ 0. 274 8, r2 = 0. 997 5 ） was obtained using m/z 194 as quantifying ion. The intra- and inter-day precisions were less than 3.99%, 5.64%, respectively. Recoveries ranged from 92. 59% to 101.27%. LLOQ was 50ng/mL. We found that reduzates of diquat were cis-trans-isomer, and their peak area ratio was 1 ： 5.3, with RSD% = 13.1% （ n = 17 ）. Conclusion The method is sensitive, simple and rapid. It is recommendable for biological samples.