QuEChERS/UPLC-MS/MS法快速测定土壤中吡虫啉、啶虫脒与阿维菌素残留

[目的]建立了热带农业区水稻-辣椒轮作模式下辣椒种植季土壤中吡虫啉、啶虫脒与阿维菌残留同时快速检测方法。[方法]样品经乙腈-0.1%甲酸(V/V)提取、N-丙基乙二胺(PSA)与C₁₈混合分散剂净化,利用超高效液相色谱串联质谱(UPLC-MS/MS)与基质溶液匹配的外标法定量分析。[结果] 3种目标农药线性范围均超过3个数量级;3种添加质量分数(1.0、10.0、100.0μg/kg),土壤中3种农药平均回收率为63.7%～89.9%,相对标准偏差(RSD,n=3)为0.1%～13.6%;方法检出限(LOD,S/N=3)为0.06～0.26μg/kg,定量限(LOQ,S/N=10)为0.21～0.89μg/kg,均低于中国、欧盟辣椒中推荐最大残留限量值检测浓度。[结论]方法快速、简便、灵敏度高、重现性好,可满足实际检测需求。

Rapid Determination of Avermectin,Imidacloprid and Acetamiprid Residues in Soil by QuEChERS/UPLC-MS/MS

[Aims] A simultaneous analysis method was optimized for the rapid determination of 3 kinds of pesticide residues in tropical soil under rice-vegetables rotation using QuEChERS-ultra-high performance liquid chromatographymass spectrometry(QuEChERS/UPLC-MS/MS). [Methods] The avermectin, imidacloprid and acetamiprid residues were effectively extracted with acetonitrile-0.1% formic acid(by vol), and then were simultaneously detected by external standard method after being purified with the mixed solid-phase dispersion of N-propylethylenedia-mine(PSA) and C18.[Results] The linear ranges were over 3 orders of magnitude for 3 kinds of pesticides. Under the three spiked levels of 1.0, 10.0 and 100.0 μg/kg, the average recoveries of the established method were 63.7-101.4%, with the relative standard deviation(RSD) of 0.1-13.6%(n=3). The limits of detection(LODs, S/N=3) of the established method were0.06-0.26 μg/kg, and also the limits of quantification(LOQs, S/N=10) were 0.21-0.89 μg/kg, which were all lower than concentration of the maximum residual limits for pepper recommended from China and UN. [Conclusions] The established method was rapid, easy operation, good sensitivity and reproducibility, could meet actual sample requirements for detection of pesticide residues.