MSPD/UPLC-TOFMS法测定草莓中4种有机磷农药残留

Determination of 4 Pesticide Residues in Strawberry Using MSPD/UPLC-TOFMS

[日的]建立利用超高效液相色谱一高分辨飞行时间质谱同时检测草莓中敌敌畏、毒死蜱、乐果、氧乐果4种有机磷农药残留的方法。[方法]试样经改进的基质固相分散法进行前处理，超高效液相色谱一高分辨飞行时间质谱法测定，外标法定量。[结果]4种有机磷农药在质量浓度10-250μg／L范围内线性关系良好（r^2〉0．99），定量下限均为10gg／kg，平均加标回收率为78％-107％，相对标准偏差为3．4％-8．6％。[结论]该方法简便、快捷、可靠、稳定，可用于草莓中敌敌畏、毒死蜱、乐果、氧乐果4种有机磷农药的快速检测与确证。

[Aims] An ultra performance liquid chromatography（UPLC）-high resolution time-of-flight mass spectrometer（TOFMS） method was developed for the simultaneous determination of dichlorvos, chlorpyrifos, omethoate, and dimethoate residues in strawberry. [Methods] The improved matrix solid-phase dispersion （MSPD） method was used for sample pretreatment. The sample was detected by UPLC-TOFMS and quantified with external standard method. [Results] The calibration curves of 4 organic phosphorous pesticides were linear in concentration range from 10 to 250 μg/L with correlation coefficients above 0.99. The limit of detection was 10 μg/kg. The average recoveries from vegetable at spiked concentration levels ranged from 78 to 107%. The relative standard deviations of the method were between 3.4 and 8.6%. [Conclusions] This method was simple, efficient and accurate. Therefore, it was practicable in the trace determination of dichlorvos, chlorpyrifos, omethoate, and dimethoate in strawberry.