分散固相萃取-液相色谱-串联质谱法测定谷物、蔬菜、水果中27种新型杀菌剂

建立了同时检测谷物、蔬菜和水果中27种新型杀菌剂的分散固相萃取-液相色谱-串联质谱(DSPE-LC-MS/MS)分析方法。样品经1%(体积分数)乙酸丙酮溶液提取,以无水硫酸镁(MgSO_4)脱水,经N-丙基乙二胺(PSA)、C_(18)、无水MgSO_4、多壁碳纳米管(MWCNT)混合净化剂净化,经C_(18)色谱柱分离,用乙腈和体积分数为0.1%的甲酸水溶液(含5 mmol/L乙酸铵)梯度洗脱,多反应监测(MRM)正离子模式扫描,采用外标法定量。噻呋酰胺和氯啶菌酯在20.47~200μg/kg范围内线性关系良好,其他25种新型杀菌剂在0.02~100μg/kg范围内线性关系良好,相关系数R~2≥0.995 0,加标回收率为70.02%~117.6%,相对标准偏差(RSD)为0.01%~19.62%(n=3)。噻呋酰胺和氯啶菌酯的检出限为6.15~16.67μg/kg,定量限为20.47~55.5μg/kg。其他25种新型杀菌剂的检出限为0.006~4.44μg/kg,定量限为0.02~14.79μg/kg。该方法简便、快速、可靠,可用于谷物、蔬菜、水果中27种新型杀菌剂的快速测定。

Determination of 27 new fungicides in cereals,vegetables and fruits by dispersive solid phase extraction and liquid chromatography-tandem mass spectrometry

A method for simultaneous determination of 27 new fungicides in cereals, vegetables and fruits using dispersive solid phase extraction and liquid chromatography-tandem mass spectrometry (DSPE-LC-MS/MS) was developed. Samples were extracted with acetone containing 1% (v/v) acetic acid, purified by a mixed sorbent of ethylenediamine-N-propylsilane (PSA), C18, anhydrous magnesium sulfate (MgSO₄) and multi-walled carbon nanotubes (MWCNT), separated by a reversed phase C18 column, and gradiently eluted with acetonitrile and 0.1% (v/v) formic acid solution (containing 5 mmol/L ammonium acetate). Anhydrous magnesium sulfate was used as a dewatering agent. The positive ion mode and multiple reaction monitoring (MRM) mode were used in the analysis, and the analytes were quantified by external standard method. Thifluzamide and triclopyricarbe showed good linearities in the range of 20.47-200 μg/kg, and the limits of detection (LODs) and the limits of quantification (LOQs) were 6.15-16.67 and 20.47-55.5 μg/kg, respectively. The other 25 new fungicides showed good linearities in the range of 0.02-100 μg/kg, and the LODs and LOQs were 0.006-4.44 and 0.02-14.79 μg/kg, respectively. The linear relative coefficients were not less than 0.9950. The recoveries were in the range of 70.02%-117.6% and the relative standard deviations (RSDs) ranged from 0.01% to 19.62% (n=3). The method has the advantages of simplicity, rapidity, high sensitivity and better purification effect. It is suitable for the rapid determination of the 27 new fungicides in cereals, vegetables and fruits.