土壤中氨基甲酸酯类农药检测的方法优化

Optimization of Methods for the Detection of Urethane Pesticides in Soil

为高效准确地测定土壤中10种氨基甲酸酯类农药,研究建立一种适用于土壤中10种氨基甲酸酯类农药含量的柱后衍生-液相色谱快速检测方法。试验优化提取条件、固相萃取柱和色谱条件,结果表明:水浴温度35℃,提取液为V(甲醇)∶V(二氯甲烷)=1∶1,提取体积为50 mL、超声时间25 min,采用Carb/NH_(2)固相萃取柱净化,选择Shim-pack FC-ODS(75 mm×4.6 mm,3μm)液相色谱柱分析测试。本检测方法的线性系数均可达到0.9993以上;线性范围为0.02~10μg/mL;检出限均小于2.0μg/kg;对10.0 g左右的土壤进行低(5μg/kg)、中(50μg/kg)、高(500μg/kg)三个浓度水平的加标测试时,10种氨基甲酸酯类农药的加标回收率为75.7%~118.5%;重现性良好,相对标准偏差为0.8%~6.8%;该方法能够满足测定土壤中10种氨基甲酸酯类农药的需要。

In order to determine 10 carbamate pesticides in soil efficiently and accurately,a rapid post-column derivation-liquid chromatography method was developed for the determination of 10 carbamate pesticides in soil.Experimental optimized of extraction conditions,solid phase extraction column and chromatographic conditions.The results showed that the extraction temperature was 35℃,the extraction liquid was methanol:dichloromethane=1∶1,the extraction volume was 50 mL,and the ultrasonic time was 25 min.Carb/NH_(2)solid phase extraction column was used for purification,and Shim-pack FC-ODS(75 mm×4.6 mm,3μm)liquid chromatographic column was selected for analysis.The linear coefficient of the method can reach above 0.9993.The linear range was 0.02~10μg/mL.Detection limits were all less than 2.0μg/kg.The recoveries of 10 carbamate pesticides ranged from 75.7%to 118.5%when the concentrations of 10.0 g soil were tested at low(5μg/kg),medium(50μg/kg)and high(500μg/kg).The reproducibility was good,and the relative standard deviation was 0.8%~6.8%.The method can meet the requirement of determining 10 kinds of carbamate pesticides in soil.