QuEChERS-超高效液相色谱-串联质谱法测定牛乳中的氟吡呋喃酮及其代谢物

Determination of Flupyradifurone and Its Metabolites in Milk Using QuEChERS and Ultra-high Performance Liquid Chromatography-Tandem Mass Spectrometry

建立同时快速测定牛乳中氟吡呋喃酮及其代谢物6-氯烟酸和二氟乙酸的超高效液相色谱-串联质谱分析方法。牛乳样品前处理采用简单高效的分散式固相萃取法(QuEChERS)净化,并对净化策略进行了评估,经改进的QuEChERS处理后,以乙腈-水(含0.1%甲酸)为流动相在Shim-pack-GIST C_(18)色谱柱上进行分离,多反应监测模式测定,基质标准曲线外标法定量。在优化的条件下,氟吡呋喃酮、6-氯烟酸、二氟乙酸分别在0.005~0.5、0.005~0.5、0.025~2.5 mg/L质量浓度范围内线性关系良好(R^(2)>0.996),在3个添加水平条件下的平均加标回收率为70.2%~97.6%,相对标准偏差为3.6%~5.3%,检出限为0.01~0.05 mg/kg。该方法操作简单、准确度和灵敏度高、重现性好,定量限远低于国家规定的最高限量,适用于大批量牛乳样品中氟吡呋喃酮及其代谢物残留的准确测定,实验结果为监管提供了可靠的技术支撑。

A rapid method was developed for the simultaneous determination of flupyradifurone and its metabolites 6-chloronicotinic acid and difluoroacetic acid in milk using ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).A simple and efficient dispersive solid phase extraction method was used to purify milk samples,and the purification strategy was evaluated.After improved quick,easy,cheap,effective,rugged and safe(QuEChERS)treatment,0.1%formic acidin acetonitrilewas used as the mobile phase for chromatographicseparation on a Shim-pack-GIST C_(18) column(100mm×2.1mm,1.7μm),and the detection was performed in themultiple reaction monitoring(MRM)mode.Theexternal standard methodwith matrix standard curveswas used for quantification.The results showed that under the optimal conditions,good linearity(linear correlation coefficient greater than0.996)was observed for flurofuranone,6-chloronicotinic acid and difluoroacetic acid in the concentration ranges of 0.005–0.5,0.005–0.5 and 0.025–2.5mg/L,respectively.The average recoveries of flupyradifurone and its metabolitesat three spiked concentrations varied from 70.2%to 97.6%,with relative standard deviations(RSDs)between 3.6%and 5.3%,and the limits of detection(LODs)ranged from 0.01 to 0.05 mg/kg,much lower than the national maximum residue limits.This method was characterized by high accuracy,highsensitivity,and good reproducibility.It is,therefore,suitable for large batches of milk samples,and can provide reliable technical support for the management of the pesticide flupyradifurone.