液相色谱串联质谱法快速测定鱼肉中四聚乙醛残留量

Determination of Residual Metaldehyde in Fish Meat by Liquid Chromatography with Tandem Mass Spectrometry

建立测定鱼肉中四聚乙醛残留量的液相色谱串联质谱分析方法。样品经乙腈提取,提取液经盐析后采用N-丙基乙二胺和C18填料净化,净化液经0.1%甲酸溶液稀释后进样分析。分析时采用Acquity BEH C18,以0.1%甲酸溶液和乙腈作为流动相作梯度洗脱,电喷雾正电子（ESI＋）模式电离,多反应监测（MRM）模式检测,内标法校准进行定量。四聚乙醛在0.05--5.0μg/L质量浓度范围内呈良好的线性,线性相关系数大于0.999,鱼肉样品中最低定量限为1.0μg/kg。鱼肉样品中添加1.0--2.0μg/kg的回收率在98.5%-100.8%之间,相对标准偏差均小于10%。

A method was developed for determining residual metaldehyde in fish meat by liquid chromatography with tandem mass spectrometry （LC-MS/MS）. Fish meat samples were extracted with acetonitrile and sequentially purified by salting-out method followed by solid phase extraction with PSA and Cls sorbent. After dilution with 0.1% formic acid solution, the samples were analyzed by LC-MS/MS on a Waters Acquity BEH Cls column with acetonitrile/0.1% formic acid in water as mobile phase with gradient elution. The mass spectrometer was operated using multiple reaction monitoring （MRM） in the positive ion mode. The analyte was quantified by the internal standard calibration curve method. Good linearity was obtained for metaldehyde in the concentration range of 0.05-5.0 μg/L with linear relative coefficient more than 0.999. The recoveries in fish meat were 98.5%-100.8% at fortified levels of 1.0-2.0μg/kg with a limit of quantitation of 1.0 μg/kg for metaldehyde. The relative standard deviations of intra-assay and inter-assay were below 10%. The method was demonstrated to be suitable for the determination of metaldehyde in fish meat.