QuEChERS-超高效液相色谱-串联质谱法测定果蔬中螺虫乙酯、丁醚脲及代谢物残留

Residue of spirotetramat, diafenthiuron and their metabolites in fruits and vegetables by QuEChERS-ultra performance liquid chromatography-tandem mass spectrometry

建立了QuEChERS前处理-超高效液相色谱-串联质谱(UPLC-MS/MS)测定果蔬中螺虫乙酯、丁醚脲及其6种代谢物(螺虫乙酯-烯醇、螺虫乙酯-烯醇-糖苷、螺虫乙酯-单羟基、螺虫乙酯-酮-羟基、丁醚脲-脲和丁醚脲-甲酰胺)残留量的分析方法。样品经破壁机匀浆,V(乙腈):V(甲酸)=10:1混合溶液涡旋提取,定制的QuEChERS净化管净化,岛津Shim-pack XRODS色谱柱分离(75 mm×2.0 mm,1.6μm)。采用电喷雾离子源正离子多反应监测模式进行质谱检测,外标法定量。丁醚脲-脲和丁醚脲-甲酰胺在0.001～0.1 mg/L范围内线性关系良好,其他6种化合物在0.005～0.5 mg/L范围内线性关系良好,R2≥0.999 3。验证了梨、葡萄、西瓜、芥蓝、芹菜和韭菜6种基质下方法的准确度和精密度,在0.001～0.5 mg/kg添加水平下,8种化合物的平均回收率在68%～94%之间,相对标准偏差在5.4%～15%之间,定量限为0.001～0.005 mg/kg。该方法简便、快速、可靠,适用于同时测定果蔬中上述8种化合物残留。

A method was developed for the quantitative determination of spirotetramat,diafenthiuron and their metabolite residues(spirotetramat-enol,spirotetramat-enol-glucoside,spirotetramat-monohydroxy,spriotetramat-keto-hydroxy,diafenthiuron-urea,diafenthiuron-amide)by QuEChERS-ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The samples were homogenized,extracted with V(acetonitrile):V(formic acid)=10:1,and cleaned-up by custom QuEChERS tubes.The separation was performed on a Shimadu Shim-pack XR-ODS column(75 mm×2.0 mm,1.6μm).The compounds were identified by MS/MS in positive electrospray ionization(ESI^+)and multiple reaction monitoring(MRM)mode,and quantified by external standard method.The linearities of diafenthiuron-urea and diafenthiuron-amide ranged from 0.001 to 0.1 mg/L.And that of the other six compounds ranged from 0.005 to 0.5 mg/L,with the correlation coeffecients higher than0.999 3.At the fortified level from 0.001 mg/kg to 0.5 mg/kg in pear,grape,watermelon,kale,celery and leek,the average recoveries of all the eight compounds ranged from 68%to 94%with the relative standard deviations varied from 5.4%to 15%.The limits of quantification(LOQ)of the analytes were0.001-0.005 mg/kg.The method is simple,rapid,accurate and suitable for the confirmation and quantification of those eight compounds in fruits and vegetables.