改进的QuEChERS气相色谱-串联质谱法测定草莓中21种杀菌剂残留

采用改进的QuEChERS气相色谱-串联质谱法建立了检测草莓中21种杀菌剂（螺环菌胺、甲霜灵、四氟醚唑、酞菌酯、嘧菌环胺、戊菌唑、氟吡菌酰胺、氟菌唑、嘧菌胺、E-苯氧菌胺、抑霉唑、腈菌唑、醚菌酯、环氟菌胺、肟菌酯、丙环唑、环酰菌胺、氟环唑、咪唑菌酮、啶酰菌胺、嘧菌酯）残留的方法。样品经乙腈提取，采用N-丙基乙二胺（primary secondary amine，PSA）和石墨化碳黑（graphitized carbon blacks，GCB）作为分散固相萃取（dispersive solid phase extraction，DSPE）的吸附材料，净化液经氮气吹干、用V（正己烷）:V（丙酮）=9:1混合溶液定容，采用气相色谱-串联质谱（gas chromatography-tandem mass spectrometry，GC-MS/MS）测定。结果表明:在质量浓度0.005~0.2 mg/kg范围内，21种杀菌剂与对应的峰面积间呈良好的线性关系；在0.01、0.05和0.1 mg/kg 3个添加水平下，21种杀菌剂的平均回收率均在70%~122%之间，RSD < 20%。该方法适用于草莓中21种杀菌剂残留的快速、高效和准确分析。

Residues of 21 fungicides in Fragaria ananassa by modified QuEChERS and gas chromatography-tandem mass spectrometry

In order to determine 21 fungicides (spiroxamine, metalaxyl, tetraconazole, nitrothal-isopropyl, cyprodinil, penconazole, fluopyram, triflumizole, mepanipyrim, E-metominostrobin, imazalil, myclobutanil, kresoxim-methyl, cyflufenamid, trifloxystrobin, propiconazol, fenhexamid, epoxiconazole, fenamidone, boscalid, azoxystrobin) in Fragaria ananassa, the sample preparation method and GC-MS/MS analysis parameters were optimized. The sample was first extracted by acetonitrile. During the DSPE procedure, PSA and GCB were used as sorbents. After concentrated, the extract was dissolved by a mixed solvent V (hexane):V (acetone)=9:1. The extract was then determined with GC-MS/MS. Linear relationships between peak area and mass concentration of 21 fungicides were obtained in the range of 0.005-0.2 mg/kg. When the spiked levels were 0.01, 0.05 and 0.1mg/kg, the average recoveries all ranged from 70 to 122% with RSD < 20% (n=5). This method is suitable for the rapid and accurate detection of 21 fungicides in F. ananassa.