同位素稀释-高效液相色谱-线性离子阱质谱法测定总膳食乳类样品中8种三嗪类农药

本试验旨在建立用同位素稀释-高效液相色谱-串联线性离子阱质谱法（HPLC-LIT-MS）同时测定总膳食乳类样品中8种三嗪类农药的检测方法。在中国144个采样点采集总膳食乳类样品,在待测样品中加入氘代同位素内标,用乙腈经超声提取,凝胶渗透色谱（GPC）净化。以乙腈和含10 mmol/L甲酸铵和0.1%甲酸的水溶液为流动相,目标化合物经CAPCELL PAK CR 1：20色谱柱分离,采用电喷雾电离,选择反应监测（SRM）正离子模式监测二级子离子。以一一对应的氘代同位素为内标物,内标法定量,计算样品中三嗪类农药的含量。总膳食乳类样品中8种三嗪类农药的平均添加回收率为83.9%~103.3%;相对标准偏差为2.5%~9.1%;检出限（LODs）为0.003~0.300 μg/kg。结果表明,该方法精密度和准确度均满足总膳食乳类样品中8种三嗪类农药的膳食暴露评估要求。

Simultaneous Determination of 8 Triazine Pesticides in Milk and Dairy Products from Total Diet by Isotope Dilution-High Performance Liquid Chromatography-Linear Ion Trap Mass Spectrometry

A method of the determination for 8 triazine pesticides in milk and dairy products from total diet was developed by isotope dilution-high performance liquid chromatography-linear ion trap mass spectrometry (HPLC-LIT-MS).Milk and dairy products from total diet were collected from 144 locations in China.Samples were ultrasonically extracted with acetonitrile,and then passed through gel permeation chromatography (GPC) to clear-up.The LC separation was performed on a CAPCELL PAK CR 1:20 column using acetonitrile and 10 mmol/L formic acid/0.1% formic aqueous solution as mobile phase.The ionization of the analytes was performed by electrospray mode.Selective reaction monitoring (SRM) was used for the monitoring of MS² transitions for each compound.The one-to-one internal standards were used for quantation.The average recoveries were in the range of 83.9% to 103.3%.The relative standard deviations were 2.5% to 9.1%.The limits of detection (LODs) were 0.003 to 0.300 μg/kg.In conclusion,the method was suitable for dietary exposure assessment of 8 triazine pesticides in milk and dairy products from total diet.