超高效液相色谱-串联质谱法测定9种绿叶类蔬菜中36种农药多残留的基质效应

应用超高效液相色谱-串联质谱法 (UPLC-MS/MS) 研究了香菜、木耳菜、油麦菜、冬苋菜、蕹菜、生菜、芹菜、菠菜和茼蒿等9种绿叶菜类蔬菜中36种农药多残留的基质效应及影响因素。比较了QuEChERS方法中不同吸附剂对基质效应的影响，并比较了经QuEChERS方法、氨基柱净化法和未经净化直接检测3种前处理方法在UPLC-MS/MS检测模式下基质效应的差异。结果表明:N-丙基乙二胺 (PSA) 对绿叶菜中主要影响基质效应的杂质净化效果较好；QuEChERS净化法优于其他2种，样品经QuEChERS法净化后，36种农药在木耳菜、油麦菜、冬苋菜、蕹菜和生菜中均为弱基质效应，可直接采用试剂标准品进行定量分析。对于基质效应明显的蔬菜和农药，建议采用基质匹配标准曲线进行定量分析；针对一些基质效应较强的农药，在灵敏度和仪器检出限允许的前提下，可适当采用稀释法补偿基质效应。

Matrix effects in the analysis of 36 pesticides residues in nine kinds of green leafy vegetables by ultra performance liquid chromatography-tandem mass spectrometry

Matrix effects and their influencing factors in the determination of 36 pesticide residues in 9 green leafy vegetables by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) were studied. The effects of different sorbents on matrix effects of the QuEChERS method were compared. And three different cleanup methods including QuEChERS, solid phase extraction on an amino column and no cleanup were comparatively evaluated. The results showed that the cleanup efficiency of PSA was better than other sorbents and was able to adsorb impurities from green leafy vegetables. QuEChERS method was better than the other two methods. After the sample was cleaned-up using QuEChERS method, matrix effects of 36 pesticides were negligible in malabar spinach, leaf lettuce, amaranth leaves, water convolvulus and lettuce, which indicated that they could be quantified using the solvent standards. For some pesticides with strong matrix effects, using matrix-matched standards was a good suggestion, and the dilution method could be used to eliminate the matrix effects if the sensitivity is high enough.