固相萃取-GC-ECD监测地表水中的溴氰菊酯、氰戊菊酯和百菌清微量残留

Determination of deltamethrin, fenvalerate and chlorothalonil microscale residues in surface water by SPE-GC-ECD

目的:建立一种固相萃取处理地表水样品,气相色谱配置ECD检测器地表水中溴氰菊酯、氰戊菊酯和百菌清微量残留的分析方法。方法:地表水样品过滤后,经HLB固相萃取柱净化,丙酮作为洗脱溶剂,残渣用正己烷定容至1mL,进样色谱系统分析。结果:溴氰菊酯、氰戊菊酯和百菌清残留在0.02~10.0μg·mL^-1浓度范围内呈良好的线性关系,相关系数均大于0.995。检出限如下:溴氰菊酯:0.012μg·L^-1,氰戊菊酯:0.008μg·L^-1,百菌清:0.006μg·L^-1。3种农残不同浓度点的回收率均在84.2%~98.7%之间。重复性与精密度相对标准偏差(n=6)均在5.0%以内。结论:该方法前处理简单,灵敏度与准确度高,适用于地表水中溴氰菊酯、氰戊菊酯和百菌清残留的监测。

OBJECTIVE To establish solid phase extracted surface water,GC-ECD method for determination of deltamethrin,fenvalerate and chlorothalonil microscale residues in surface water.METHOD After filtered,surface water samples were purified by HLB SPE column,acetone was selected as eluted solution,the residue was volumetric with n-hexane to 1mL,and analysed on gas chromatography system.RESULT The concentration of deltamethrin,fenvalerate and chlorothalonil residues had good linear relationships in the range 0.02~10.0μg·mL-1,with correlation coefficients(R2)were all above 0.995.Detection limits were as follows:deltamethrin:0.012μg·L^-1,fenvalerate:0.008μg·L^-1,and chlorothalonil:0.006μg·L^-1.The recoveries at 3 different levels were ranged from 84.2%~98.7%.RSD of reproducibility and precision were all below 5.0%(n=6).CONCLUSION The method has simple pretreatment,high sensitivity and accuracy,which is suitable for the detection of deltamethrin,fenvalerate and chlorothalonil in surface water.