液相色谱-串联质谱法快速测定果蔬中16种新型酰胺类杀菌剂残留量

Fast Simultaneous Determination of Sixteen Novel Amide Fungicides in Vegetables and Fruits by Liquid Chromatography-Tandem Mass Spectrometry

建立果蔬(白菜、芹菜、草莓和葡萄)中16种新型酰胺类杀菌剂的液相色谱-串联质谱快速分析方法。样品用乙腈提取和氯化钠盐析分层后,上清液直接用0.1%甲酸溶液稀释10倍后进行液相色谱-串联质谱分析。采用Acquity BEH C18色谱柱分离,用0.1%甲酸溶液-乙腈作为流动相进行梯度洗脱,电喷雾正离子模式电离,多反应监测模式检测,基质校准外标法定量。各物质峰面积与样品质量浓度在2.5×10-4~0.25 mg/L范围内呈良好的线性关系,线性回归系数不低于0.994 9。在添加量0.01~5.0 mg/kg范围内,4种果蔬加标16种杀菌剂的平均添加回收率在85.7%~103.9%范围内,批内相对标准偏差在2.6%~5.2%之间。16种新型酰胺类杀菌剂的检出限为1.0×10-4~3.0×10-3 mg/kg,定量限为3.0×10-4~0.01 mg/kg。该方法能满足果蔬中16种新型酰胺类杀菌剂残留量分析的要求。

A fast method was developed for simultaneously determining 16 novel amide fungicides in fruits and vegetables using liquid chromatography tandem mass spectrometry(LC-MS-MS). Samples were extracted with acetonitrile and saltedout by sodium chloride to partition amide fungicides into the upper acetonitrile layer. The upper supernatant was then directly diluted with 0.1% formic acid solution before being analyzed by LC-MS-MS on an Acquity BEH C18 column with a mixture of 0.10% formic acid solution(A) and acetonitrile(B) as the mobile phase under gradient elution conditions. The mass spectrometer was operated in the positive ion mode using multiple-reaction monitoring(MRM). The target analytes were quantified by matrix-matched external standard calibration. There was a good linear correlation with calibration coefficients all above 0.994 9 between the peak areas and concentrations of the amide fungicides in the range of 2.5 × 10-4 to 0.25 mg/L. The average recoveries of the 16 compounds in cabbage, celery, strawberry and grape were 85.7%–103.9%, and the intra-assay relative standard deviations(RSDs) were between 2.6% and 5.2%. The limits of quantification(LOQs) of these fungicides varied from 3.0 × 10-4 to 0.01 mg/kg. The proposed method was demonstrated to be suitable for the determination of the 16 amide fungicides in vegetables and fruits.