改良QuEChERS-GC-TQT/MS法测定大米中16种有机磷农药残留

Determination of 16 Organophosphorus Pesticide Residues in Rice by Modified QuEChERS-GC-TQT/MS Method

建立同时测定大米中16种有机磷农药残留的Qu ECh ERS-加速溶剂萃取-气相色谱/三重四极杆串联质谱法。称取大米,经加压流体萃取,提取液经无水硫酸钠柱脱水后,旋蒸至近干,加入丙酮溶解后吸取一定样液至多农残净化管中净化,氮吹,丙酮复溶后,供GC-TQT/MS测定。结果表明,16种有机磷农药在质量浓度0.01~1μg/m L的基质曲线范围内呈良好线性关系,相关系数R^(2)大于0.99,在7.5,15和100μg/kg 3个浓度水平(n=6)的加标回收率为78.8%~103.8%,相对标准偏差(S_(RSD))为1.32%~7.78%。方法检出限(SLOD)为2.94~6.83μg/kg,方法定量限(S_(LOQ))为11.44~14.37μg/kg。该方法具有操作简便、快速高效、回收率高、灵敏度高、重复性好等优点,可用于测定大米中16种有机磷农药残留量。

A QuEChERS-accelerated solvent extraction-gas chromatography-triple quadrupole tandem mass spectrometry method for the simultaneous determination of 16 organophosphorus pesticide residues in rice was established.The rice was weighed and extracted by pressurized fluid.After the extract was dehydrated by an anhydrous sodium sulfate column,it was rotary evaporated to near dryness.After being dissolved in acetone,a certain sample solution was drawn into a pesticide residue purification tube for purification,after nitrogen blowing and acetone redissolving,for GC-TQT/MS determination.The 16 organophosphorus pesticides showed a good linear relationship in the range of the matrix curve with a concentration of 0.01-1μg/m L;The correlation coefficient R^(2) was greater than 0.99,and the spiked recoveries at 7.5,15 and 100μg/kg(n=6)were 78.8%-103.8%.The relative standard deviation(SRSD)ranged from 1.32% to 7.78%.The limit of detection(SLOD)were 2.94-6.83μg/kg,and the limit of quantitation(S_(LOQ))were 11.44-14.37μg/kg.The method had advantages of simple operation,rapidity and efficiency,high recovery rate,high sensitivity and good repeatability,and could be used for the determination of 16 organophosphorus pesticide residues in rice.