水样中几种酰胺类除草剂的SPE-GC/ECD法检测

采用固相萃取-气相色谱/电子捕获检测法(SPE-GC/ECD)对水样中的几种酰胺类除草剂(含两种三嗪类除草剂)进行了残留量检测.并对实验过程中涉及的一系列条件进行了优化,结果表明:C18小柱经5 mL甲醇-5 mL水活化后,将样品以约4～5 mL/min的速率过柱富集;再用13～15 mL丙酮、以约0.4～0.5 mL/min的速率进行洗脱,洗脱液旋转蒸发浓缩N_2吹除水后用正己烷定容后上机测定,结果良好,符合有机分析要求.仪器的检出限为0.003～0.056 mg/L.

Method for detection of acetanilide herbicide residues in water sample by SPE-GC/ECD

Several kinds of acetanilide herbicide residues in water sample were detected by SPE-GC/ECD(solid phase extraction-gas chromatography/electron capture detector).Correlative test conditions were optimized during experimentation.The results showed that the said SPE-GC/ECD method was an appropriate one for detecting acetanilide herbicide residues in water sample under the following conditions:The SPE C18 column was activated by injecting 5 mL of methanol-5 mL of ultra-pure water;then the water sample was routed through the C18 column at a rate of 4～5 mL/min in order to retain the target compounds in the column;and then 13～15 mL of acetone passed through the column at a rate of 0.4～0.5 mL/min for desorption of target compounds;finally,the washing solution was concentrated and purged by nitrogen until being approximately dry,and then was diluted to a constant volume with hexane prior to detection by GC/ECD.The detection limits of these acetanilide herbicides on GC/ECD varied from 0.003～0.056 mg/L.