GC-MS法测定蔬菜中3,5,6-三氯-2羟基吡啶

Determination of 3, 5, 6-Trichloro-2-pyridinol in Vegetables by Gas Chromatography-Mass Spectrometry

建立蔬菜中毒死蜱代谢物3,5,6-三氯-2羟基吡啶(3,5,6-trichloro-2-pyridinol,TCP)的气相色谱-质谱检测方法。样品经丙酮提取,正己烷去除杂质,二氯甲烷反萃取,过无水硫酸钠去除水分,浓缩后乙酸乙酯溶解,再用N-(特丁基二甲基硅烷基)-N-甲基三氟乙酰胺(MTBSTFA)衍生,正己烷定容,经气相色谱-质谱检测,外标法定量。方法的检出限为8.3μg/kg,加标回收率为70.4%～107.6%,RSD为4.3%～8.7%。在5～500μg/L的范围内线性范围良好,相关系数大于0.99。该方法通用性强,灵敏度高,可用于蔬菜中TCP的检测。

A gas chromatography-mass spectrometry （GC-MS） method was established for the determination of 3,5,6-trichloro-2-pyridinol （TCP）, a kind of metabolite of chlorpyrifos in vegetables. The sample was extracted by acetone, and the extract was purified using hexane and DCM. The water was removed with anhydrous sodium sulfate. After condensation, the extract was dissolved into 1 mL of ethyl acetate and then derivatized with N-（tert-butyldimethylsilyl）-methyltrifluoroacetamide （MTBSTFA）, and finally the volume was adjusted to 1 mL using hexane. The analyte was detected by GC-MS, and an external standard method was used for quantifying TCP. The limit of detection was 8.3μg/kg, and the recovery rates of spiked sample were in the range of 70.4%-107.6% with relative standard deviation of 4.3%-8.7%. An excellent linear relationship was achieved in the range of 5-500μg/L with correlation coefficients over 0.99. This method is characteristics of accuracy, easy operation and can be applied for determining TCP in vegetables.