液相色谱-串联质谱法检测蜂蜜中杀虫脒及其代谢产物残留

Determination of chlordimeform and its metabolite residues in honey using liquid chromatography-tandem mass spectrometry

建立了液相色谱-串联质谱分析洋槐蜜、荆条蜜、蜂巢蜜、杂花蜜、野蜂蜜中杀虫脒及其代谢产物残留的方法。样品经氢氧化钠水溶液稀释溶解后,采用WatersOasisHLB固相萃取柱净化。样品提取液经AgilentXDB-C18色谱柱分离,以0.1%甲酸水溶液和乙腈为流动相进行梯度洗脱。以电喷雾正离子(ESI+)模式电离,多反应监测(MRM)模式检测,基质匹配标准溶液外标法定量。杀虫脒及其代谢产物(4-氯邻甲苯胺)在2.5～250μg/L范围内呈线性相关,相关系数(r)均大于0.999;定量限(S/N>10)为5μg/kg,检出限(S/N>3)为2.5μg/kg。各种蜂蜜基质样品在5、10和20μg/kg添加水平时,杀虫脒及其代谢产物的回收率范围分别为75.8%～113.8%和85.6%～114.3%,相对标准偏差(RSD)分别为4.8%～10.2%和4.7%～9.1%,可以满足蜂蜜中杀虫脒及其代谢产物残留量的检测需要。

A liquid chromatography-tandam mass spectrometry （LC-MS/MS） method was developed for the determination of chlordimeform and its metabolite （4-chloro-o-toluidine） residue in acacia honey,chaste honey,comb honey,multifloral honey and wild honey.The samples were dissolved and diluted with sodium hydroxide solution,and cleaned up by a Waters Oasis HLB solid phase extraction column.The separation was performed on an Agilent XDB-C18 column with gradient elution using 0.1% formic acid solution and acetonitrile.The residues of chlordimeform and its metabolite were determined by electrospray ionization-tandem mass spectrometry,and quantified by the method of matrix-matched external standard.The calibration curves for chlordimeform and its metabolite showed good linearity in the range of 2.5-250 μg/L with the correlation coefficients （r） higher than 0.999.The limit of quantification was 5 μg/kg,and the limit of detection was 2.5 μg/kg.The recoveries of chlordimeform and 4-chloro-o-toluidine in honey at the spiked levels of 5,10 and 20 μg/kg were in the ranges of 75.8%-113.8% and 85.6%-114.3%,respectively.The relative standard deviations were 4.8%-10.2% and 4.7%-9.1%,respectively.The method can meet the requirements for the determination of chlordimeform and 4-chloro-o-toluidine in honey for import and export inspection.