高效液相色谱-串联质谱法测定动物源性食品中噻节因残留

Determination of dimethipin residues in animal derived food by HPLC-MS/MS

建立了高效液相色谱-串联质谱测定动物源性食品中噻节因残留的分析方法。样品经体积分数1%的乙酸乙腈溶液提取、正己烷脱脂、C 18固相萃取柱净化,采用Venusil MP C 18(2)色谱柱(150 mm×2.1 mm,3μm)分离,以乙腈和水为流动相进行梯度洗脱,采用大气压化学电离源电离、负离子模式扫描,多反应监测模式检测,内标法定量。结果表明:噻节因质量浓度在1.0~500.0μg/L范围内呈良好线性,相关系数(R 2)为0.9993,方法的定量限为1.0μg/kg;以猪肉、猪肝、牛肉、牛肝、羊肉、羊肝、鸡肉、鸡胗、鸡蛋和牛奶为基质,噻节因在1.0、10.0和100.0μg/kg 3个水平下的平均加标回收率为89.0%~105.0%,相对标准偏差为2.20%~7.64%。该方法基质干扰小、灵敏度高、准确可靠、适用于动物源性食品中噻节因残留的定量检测。

A method for the determination of dimethipin residues in animal derived food by high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)was developed.The samples were extracted with acetonitrile containing 1%(V/V)acetic acid and defatted with n-hexane,followed by clean-up using C 18 solid phase extraction column.The analytes were separated on a Venusil MP C 18(2)column(150 mm×2.1 mm,3μm)under a gradient elution program using acetonitrile and water was used as the mobile phases.The analytes were detected by tandem mass spectrometry using a negative atmospheric pressure chemical ionization(APCI-)source in the multiple reaction monitoring(MRM)mode.The internal standard calibration curves were used for quantitative analysis.The results showed that calibration curves had good linearities in the range of 1.0-500.0μg/L for dimethipin,which with a correlation coefficients(R 2)0.9993.The limit of quantification(LOQ)of the method was 1.0μg/kg.The average recoveries of dimethipin in pork,pig liver,beef,beef liver,mutton,sheep liver,chicken,chicken gizzard,egg and milk matrices at spiked levels of 1.0,10.0 and 100.0μg/kg were 89.0%-105.0%,and the relative standard deviations were 2.20%-7.64%.The method has less matrix interference,with high sensitivity,accuracy and reliability,and it is suitable for the quantitative detection of dimethipin residues in animal derived food.