高效液相色谱测定咯菌腈在葡萄和土壤中的残留行为

Determination of Residual Behavior of Fludioxonil in Grape and Soil by HPLC

建立了咯菌腈在葡萄和土壤中的高效液相色谱的残留分析方法,并在安徽和河北进行了 40%咯菌腈悬浮液在葡萄上残留的田间试验,研究了咯菌腈在葡萄和土壤中的消解动态和最终残留量。葡萄样品通过二氯甲烷提取,弗罗里硅土小柱净化;土壤样品通过乙腈提取,QuEChERS方法净化,采用高效液相色谱(HPLC)检测。在0.05~10mg/L在范围内,咯菌腈质量浓度与对应的峰面积间呈良好线性关系,线性方程为y=30.951%-0.417 1, R^2=0.999 8,在0.02、0.2和2mg/kg3个添加水平下,咯菌腈在葡萄和土壤中的平均回收率为88.2%-95.8%,相对标准偏差为0.8%~7.1%,最小检出量为5×10^-10g,最低检测浓度为0. 02mg/kg。田间试验结果表明:40%咯菌腈悬浮液在葡萄和土壤中的半衰期分别为5.6~8.0d和6.0~9.8d。最终残留量测定结果显示40%咯菌腈悬浮剂,用于防治葡萄灰霉病,施药剂量不超过133.3mga.i./kg (制剂3 000倍液),最多施药3次,安全间隔期为7d。

A high performance liquid chromatography method was established for the determination of fludioxonil residues in giape and soil, and the field trials were earned out at two locations in Anhui and Hebei to evaluate the dissipation and residue of fludioxonil in grape and soil. The grape samples were extracted by dichloromethane and purified by Florisil column. The soil samples were extracted by acetonitrile, purified by QuEChERS and detected by HPLC. The result showed that a good linear relationship was obtained between the target substance concentration and the peak area in the range of 0. 05~10 mg/L, and that the linear equation was y=30. 951x-0. 417 1 , R^2 = 0. 999 8. The average recoveries in grape and soil were from 88. 2% to 95. 8% at the fortified level of 0. 02 mg/kg to 2 mg/kg, and the relative standard deviation was between 0. 8% to 7. 1 %. The limit of detection was 5×10^-10g and the limit of quantification was 0. 02mg/kg. The field test results showed that the half-lives of fludioxonil were 5. 6 to 8. 0 days in grape and 6. 0 to 8. 9 clays in soil. The final residue results showed that fludioxonil 40% SC can be used for the control of grape botrytis cinerea with the dosage of less than 133. 3mg a. i./kg (3 000 times dilution), the maximum 3 times application and the safe interval of 7d.