超高效液相色谱法测定土壤中多杀菌素和乙基多杀菌素的残留

建立了土壤中多杀菌素(spinosad)A和D以及乙基多杀菌素(spinetoram)J和L残留量的超高效液相色谱(UPLC)检测方法。土壤样品经乙腈-5%氯化钠溶液-1 mol/L氢氧化钾溶液提取,固相萃取柱净化,UPLC检测,外标法定量。结果表明:土壤中多杀菌素和乙基多杀菌素的定量限分别为0.1和0.05 mg/kg;最小检出量分别为8.0×10-7和2.8×10-7g;在0.1~2 mg/kg添加水平下,多杀菌素在土壤中的平均回收率为89%~96%,相对标准偏差(RSDs)为2.1%~4.9%;在0.05~0.5 mg/kg添加水平下,乙基多杀菌素在土壤中的平均回收率为86%~93%,RSDs为1.2%~8.1%。该方法提取效果好,具有良好的灵敏度、回收率和重复性。

Determination of spinosad and spinetoram residues in soil by ultra performance liquid chromatography(UPLC)

An ultra performance liquid chromatography(UPLC) method was established for the determination of spinosad(A and D) and spinetoram(J and L) residues in soil. The soil samples were extracted with acetonitrile-5% NaCl-1 mol/L KOH and purified by SPE tube. The final extract was injected into UPLC and quantified by external standard method. According to the results of experiments, the limits of quantification(LOQs) were 0.1 and 0.05 mg/kg for spinosad and spinetoram respectively, and the limits of detection of spinosad and spinetoram were 8.0×10^-7 and 2.8×10^-7 g respectively. The recoveries of spinosad spiked in soil were 89%-96% with the relative standard deviations(RSDs) ranging from 2.1% to 4.9%, and the recoveries of spinetoram spiked in soil were 86%-93% with the RSDs ranging from 1.2% to 8.1%. The results have demonstrated that the proposed method is sensitive and accurate for the determination of spinosad and spinetoram in soil.