固相萃取-高效液相色谱柱后衍生法测定水中痕量N-甲基氨基甲酸酯

Simultaneous determination of trace N-methycarbamates pesticides in water by solid-phase extraction and HPLC with post-column derivatization

目的：建立简便、灵敏、准确的测定水中11种痕茸N-甲基氨基甲酸酯类农药及其代谢产物的固相萃取、高液相色谱柱后衍生的检测方法。方法：水样经ODS—C18小柱富集、净化后，以甲醇／TL／乙腈为流动相，在Waters氨基甲酸酯类农药分析专用柱（3．9mm×150mm）上进行梯度洗脱分离，然后再在碱性条件下（pH〉9．0），采用2-巯基乙醇和邻苯二甲醛（OPA）进行柱后衍生，荧光法检测（λex339nm，λem445nm）。结果：11种N-甲基氨基甲酸酯类农药及其代谢产物在50．0—1500．0μg／L范围内均具有良好的线性，水样的定量检测下限为0．10—0．73μg／L，方法回收率在91．5％～104．1％，RSD均小于7．6％。结论：该法灵敏度高、操作简便、快速，适用于实际样品的测定。

Objective：To establish a simple, sensitive and exact method for the determination of eleven trace N - methycarbamates in water by solid phase extraction and HPLC with post - column derivatization. Methods：The water samples were extracted and condensed by solid - phase extraction with ODS - C18 cartridges, and then were separated on a Carbamate Analysis HPLC column （3.9 mm×150 mm） using a gradient mobile phase consisting of CH3OH - CH3CN - H2O at a flow rate of 1.50 ml/min. Detection was performed on a fluorescence detector（ λex 339 nm ,λem 445 nm） after post - column derivazation with O - phthalaldehyde （OPA） and 2 - Mercaptoethanol （ 2 - Me） in the sodium hydroxide solution （ pH 〉 9 ）. Results ： The linear range of the eleven N - methycarbamates was 50. 0 - 1 500.0μg/L and the detection limits for quantification were 0. 10-0. 73μg/L. Extraction recoveries were between 91.5%- 104. 1%, and RSD were less than 7.6%. Conclusion：This method is found to be sensitive, fast and simple. Therefore, it can be used for the determination of the eleven trace N - methycarbamates in water samples.