气相色谱串联质谱法用于茶叶中多种农药残留的分析检测

Determination of multi-residue pesticides in tea by gas chromatography-tandem mass spectrometry

建立了茶叶中56种农药残留物质的检测,样品采用改进后的GB/T 23204-2008的方法处理,乙腈均质提取,旋转浓缩后过固相萃取柱净化,洗脱液经氮气吹至近干,乙酸乙酯定容,过膜后供GC-MS-MS分析。对茶叶样品进行不同水平的加标回收实验,得到物质的回收率在73.2%~116%之间,RSD在2.01%~10.8%之间,线性相关系数在0.99以上,方法的检出限为0.01mg/kg。该方法灵敏度高、准确性好,可用于实际样品的分析检测。

A method was developed to determine the multi-residual pesticides in tea by gas chromatography-tandem mass spectrometry.Samples were prepared by the improved GB/T 23204-2008 method,extracted with acetonitrile assisted by homogeneous,then concentrated to 1mL^3mL with vacuum pressure rotating enrichment apparatus.The concentrated sample was purified through solid phase extraction column subsequently,the collected eluate was blow to nearly dry with nitrogen,after that,1 mL ethyl acetate was added into the dried sample to dissolve the target material,then the solution was passed through a 0.22μm membrane filter and introduced into the chromatographic system.In the three spiked levels,the average recoveries were in the range of 73.2%~116%,with relative standard derivations between 2.01%and 10.8%.The linear range was 0.02-0.5 mg/L and the limit of detection for multi-residual pesticides were 0.01 mg/kg with the signal-to-noise ratio of 3.The results indicate this method is suitable for the actual sample testing.