改良QuEChERS方法结合高效液相色谱测定土壤中两种甲氧基丙烯酸酯类农药

Determination of 2 Strobilurin Fungicide Residues in Soil by Modified QuEChERS Method Combined with Liquid Chromatography

旨在建立新疆、内蒙、黑龙江3种不同类型土壤中醚菌酯和吡唑醚菌酯含量的高效液相色谱法。采用改良的QuEChERS方法结合高效液相色谱,对样品中的吡唑醚菌酯及醚菌酯进行分离,外标法定量。结果表明:该方法在0.3~10.0 mg/L浓度范围内,线性关系良好,线性相关系数R2均大于0.9999,在不同添加水平下,吡唑醚菌酯与醚菌酯在新疆灰漠土中的平均回收率分别为98.03%~102.32%、100.33%~107.18%,相对标准偏差(RSD)分别为0.46%~0.87%、0.94%~1.67%;在黑龙江黑钙土中的平均回收率分别为100.40%~104.32%、90.83%~101.33%,RSD分别为0.47%~2.78%、1.35%~1.69%;在内蒙棕钙土中的平均回收率分别为100.04%~107.40%、96.90%~98.86%,RSD分别为0.77%~1.41%、1.08%~1.57%。该方法准确度和精密度符合农药残留分析的要求,适用于几种类型土壤中吡唑醚菌酯及醚菌酯含量的测定。

The study aimed at establishing a high performance liquid chromatography(HPLC)method for the determination of pyraclostrobin and kresoxim-methyl in three different types of soil from Xinjiang,Inner Mongolia and Heilongjiang.The separation of pyraclostrobin or kresoxim-methyl in samples was performed by modified QuEChERS method combined with HPLC,and the quantitative results were calculated by external standard method.The results showed good linearity in the concentration ranged from 0.3-10.0 mg/L,and the correlation coefficient(R2)was greater than 0.9999.At different concentrations,the average recoveries of pyraclostrobin and kresoxim-methyl in Yermosols of Xinjiang were 98.03%-102.32%and 100.33%-107.18%with relative standard deviations(RSD)of 0.46%-0.87%and 0.94%-1.67%.The average recoveries of pyraclostrobin and kresoxim-methyl in Chernozem of Heilongjiang were 100.40%-104.32%and 90.83%-101.33%with RSD of 0.47%-2.78%and 1.35%-1.69%.The average recoveries of pyraclostrobin and kresoxim-methyl in Xerosols of Inner Mongolia were 100.04%-107.40%and 96.90%-98.86%with RSD of 0.77%-1.41%and 1.08%-1.57%.The accuracy and precision of the method meet the requirements of pesticide residue analysis,and it is suitable for the determination of pyraclostrobin and kresoxim-methyl in above types of soil.