超高效液相色谱-串联质谱法检测桃中13种高关注农药残留

Detection of 13 kinds of highly attentive pesticides residues in peach by ultra performance liquid chromatography-tandem mass spectrometry

目的建立超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)测定桃中13种高关注农药残留的分析方法。方法样品采用含1%(体积分数)乙酸的乙腈溶液超声提取, 4 g无水硫酸镁和1 g氯化钠盐析后,不净化,直接经Waters HSS T3 (2.1 mm×100 mm,1.8μm)色谱柱分离,用甲醇和2 mmol/L甲酸铵水溶液为流动相梯度洗脱,串联质谱电喷雾正离子扫描,多反应监测模式检测,基质匹配标准溶液-外标法定量。结果 13种农药在0.5~8μg/kg范围内线性关系良好,相关系数r均大于0.997,在桃中添加0.5、2和5μg/kg 3个浓度的农药标准溶液,平均回收率为63.2%~123.0%,日内相对标准偏差(relative standard deviation, RSD)为0.6%~10.3%(n=6),日间RSD为2.8%~13.2%(n=3),定量限均为0.5μg/kg。结论该方法简单、可靠、灵敏,适用于桃中13种农药残留的检测。

Objective To establish a rapid method for the simultaneous detection of 13 kinds of highly attentive pesticides residues in peach by ultra performance liquid chromatography-tandem mass spectrometry.Methods The peach samples were extracted by ultrasonic extraction with acetonitrile containing 1%acetic acid,followed by salting out with 4 g magnesium sulfate and 1 g sodium chloride without further cleanup,then separated on a Waters HSS T3(2.1 mm×100 mm,1.8μm)column by gradient elution with methanol and 2 mmol/L ammonium formate as mobile phase,ionized with positive electrospray ionization,detected under multiple reaction monitoring mode,and quantified with matrix-matched external standard calibration curves.Results There existed good linearities for 13 kinds of pesticides in the concentration range of 0.5‒8μg/kg,with correlation coefficients higher than 0.997.The average recoveries at three spiked levels of 0.5,2 and 5μg/kg in peach ranged from 63.2%to 123.0%,with intra-day relative standard deviations(RSD)of 0.6%‒10.3%(n=6)and inter-day RSD of 2.8%‒13.2%(n=3).The limits of quantification for all the analytes were 0.5μg/kg.Conclusion The proposed method is simple,accurate and sensitive,which is suitable for the detection of 13 kinds of pesticide residues in peach.