超高效液相色谱-串联质谱法测定油料作物中8种苯胺类除草剂

建立了玉米、花生等油料作物中8种苯胺类除草剂的超高效液相色谱-串联质谱检测方法。试样经乙腈超声提取后，以N-丙基乙二胺（N-propyl ethylenediamine，PSA）和无水MgSO₄净化，ZORBAX Eclipse Plus C₁₈色谱柱（2.1 mm×100 mm，1.8 μm）分离，以甲醇（含1%乙腈）和5 mmol/L乙酸铵水溶液（含0.1%甲酸）为流动相梯度洗脱，流速为0.3 mL/min。采用电喷雾离子源（ESI）正离子模式扫描，多反应监测（MRM）模式进行检测，外标法定量。结果表明，8种苯胺类除草剂在不同浓度范围内（二甲戊乐灵、仲丁灵和磺草唑胺在2.0~200 μg/L，异丙乐灵在5.0~200 μg/L，甲磺乐灵、乙酰甲草胺、氯苯胺灵和氯草灵在0.5~200 μg/L）线性关系良好，相关系数（r）均在0.999以上，在3个不同浓度加标水平下的平均回收率为69.5%~97.5%，相对标准偏差（RSD，n=5）为0.5%~9.5%。方法的检出限（LOD，S/N=3）和定量限（LOQ，S/N=10）分别为0.07~1.20和0.23~4.00 μg/kg。该方法高效、灵敏，适用于玉米和花生等油料作物中苯胺类除草剂的快速定量检测。

Determination of 8 Aniline Herbicides in Oil Crops by Ultra High Performance Liquid Chromatography-Tandem Mass Spectrometry

A method was developed for the simultaneous determination of 8 aniline herbicides in oil crops by ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The samples were ultrasonically extracted with acetonitrile,and then purified with N-propyl ethylenediamine(PSA)and anhydrous magnesium sulfate.The target compounds were separated on a ZORBAX Eclipse Plus C 18 column(2.1 mm×100 mm,1.8μm)by gradient elution using methanol(containing 1%acetonitrile)and 5 mmol/L ammonium acetate solution(containing 0.1%formic acid)as mobile phase at a flow rate of 0.3 mL/min.Qualification was achieved by positive electro-spray ionization using multiple reaction monitoring(MRM),and the external standard method was used for quantitation.The calibration curves for 8 aniline herbicides were linear in their corresponding range(2.0~200μg/L for pendimethalin,butralin and metosulam,5.0~200μg/L for isopropalin,0.5~200μg/L for nitralin,diethatyl ethyl,chlorpropham and chlorbufam)with their correlation coefficients(r)all above 0.999.The recoveries for 8 aniline herbicides at three different spiked levels were in the range of 69.5%~97.5%with relative standard deviations(RSD)of 0.5%~9.5%(n=5).The limits of detection(S/N=3)and quantitation(S/N=10)of the method were 0.07~1.20 and 0.23~4.00μg/kg,respectively.Owing to high efficiency and sensitivity,the method was suitable for rapid and simultaneous analysis of aniline herbicides in oil crops.