气相色谱-串联质谱法测定土壤中5种琥珀酸脱氢酶抑制剂类杀菌剂的残留量

Determination of Residues of 5 Succinate Dehydrogenase Inhibitor Fungicides in Soil by Gas Chromatography-Tandem Mass Spectrometry

提出了加速溶剂萃取(ASE)联合Qu ECh ERS自动样品制备系统净化,以气相色谱-串联质谱法(GC-MS/MS)同时测定土壤中甲呋酰胺、吡噻菌胺、麦锈灵、灭锈胺、呋吡菌胺等5种琥珀酸脱氢酶抑制剂类杀菌剂残留量的方法。取风干并过筛后的土壤样品10.00 g,加入5 g硅藻土,研磨均匀后转移到萃取池中,以体积比1∶2的正己烷-乙酸乙酯混合溶液进行萃取,萃取液在旋转蒸发仪上浓缩至10 m L,全部转移至Qu ECh ERS自动样品制备系统的净化管中,振荡5 min,以转速8 000 r·min^(-1)离心5 min,将2 m L上清液于50℃水浴中氮气吹至近干,用正己烷定容至1 m L。在Rxi-5Sil MS色谱柱上按照柱升温程序分离,质谱分析采用多反应监测(MRM)模式,外标法定量。结果表明,5种琥珀酸脱氢酶抑制剂类杀菌剂的质量浓度在0.005~0.1 mg·L^(-1)内与对应的峰面积呈线性关系,检出限(3S/N)为0.000 7~0.001 1 mg·kg^(-1);按照标准加入法进行回收试验,回收率为89.6%~110%,测定值的相对标准偏差(n=6)均小于5.0%。方法用于分析5份不同作物的种植土壤样品,5种琥珀酸脱氢酶抑制剂类杀菌剂均未检出。

A method for simultaneous determination of residues of 5 succinate dehydrogenase inhibitor fungicides in soil,including fenfuram,penthiopyrad,benodanil,mepronil and furametpyr,was proposed by gas chromatography-tandem mass spectrometry(GC-MS/MS) after accelerated solvent extraction (ASE) combined with Qu ECh ERS automatic sample preparation system purification.10.00 g of the dried and sieved soil sample was taken,and 5 g of diatomite was added.Affer mixing uniform,the mixture was placed in the extraction tank,and extracted with a mixed solution of hexane and ethyl acetate at a volume ratio of 1∶2.The extract was concentrated to 10 m L on a rotary evaporator and transferred to the purification tube of the Qu ECh ERS automatic sample preparation system.The mixture was oscillated for 5 min and centrifuged at a rotational speed of 8 000 r·min^(-1)for 5 min.2 m L of supernatant was blown to near drynesss by nitrogen at 50℃in water bath,and made its volume up to 1 m L with hexane.Targets in the solution was separated on a Rxi-5Sil MS chromatographic column according to the column heating program.Multiple reaction monitoring (MRM) mode was adopted in mass spectrometry analysis,and the external standard method was used for quantitative analysis.As shown by the results,linear relationships between the corresponding peak areas and mass concentrations of 5 succinate dehydrogenase inhibitor fungicides were found within 0.005-0.1 mg·L^(-1),with detection limits (3S/N)in the range of 0.000 7-0.001 1 mg·kg^(-1).Test for recovery was made by the standard addition method,giving results in the range of 89.6%-110%,with RSDs (n=6) of the determined values less than 5.0%.This method was used for the analysis of5 samples of planting soil for different crops,and 5 succinate dehydrogenase inhibitor fungicides were not detected.