改良QuEChERS/气相色谱法测定蔬菜中35种有机磷农药的残留量

Determination of 35 kinds of organophosphorous pesticide residues in vegetables by modified QuEChERS/gas chromatography

中文关键词:  QuEChERS  气相色谱法  蔬菜  有机磷农药

英文关键词:QuEChERS  gas chromatography  vegetables  organophosphorous pesticide

中文摘要:

      目的 建立改良QuEChERS/气相色谱法测定蔬菜中35种有机磷农药残留的快速分析方法。方法 样品由乙腈提取, 氯化钠盐析后, 经PSA (primary secondary amine sorbent)填料和无水硫酸镁分散固相萃取净化, 气相色谱火焰光度检测器(flame photometric detector, FDP)检测, 基质匹配标准曲线校正, 外标法定量。结果 在50.0~1000.0 μg?kg-1线性范围内线性良好, 相关系数(r)为0.9959~0.9998, 在0.08、0.20、0.40 mg?kg-1 3个添加水平下35种有机磷农药的平均回收率为75.32%~118.82%, 相对标准偏差为0.46%~5.62%, 方法检出限(limit of detection, LOD)为0.01~0.05 mg?kg-1, 定量限(limit of quantitation, LOQ)为0.03~0.10 mg?kg-1。结论 该方法简便快速、准确灵敏, 有机溶剂用量少, 可满足蔬菜中35种有机磷农药残留同时快速检测的实际需要。

英文摘要:

      Objective To establish a method for simultaneous analysis of 35 organophosphorous pesticide residues in vegetables by the QuEChERS-gas chromatography (QuEChERS-GC). Methods The samples were extracted with acetonitrile and salted out with sodium chloride. The extracts was purified by dispersive solid phase extraction using PSA and magnesium sulfate as sorbents. Gas chromatography/flame photometric detector (GC/FPD) was used for detection and matrix matching standard curve was used for correction. The external standard method was used for quantitative analysis. Results Thirty-five kinds of organophosphorous pesticides had good linearity in the range of 50.0-1000.0 μg?kg-1 and the correlation coefficients (r) ranged from 0.9959 to 0.9998. The recoveries of 35 kinds of organophosphorus pesticides ranged from 75.32% to 118.82%, with relative standard deviations (RSDs) from 0.46% to 5.62% at 3 spiked levels of 0.08、0.20、0.40 mg?kg-1. The limits of detection (LOD) were in range of 0.01-0.05 mg?kg-1. The limit of quantitation (LOQ) were in range of 0.03-0.10 mg?kg-1. Conclusion This method is simple, rapid, sensitive, with a small amount of organic solvent, which can meet the demands for the simultaneous determination of multi-residue organophosphorous pesticide residues in vegetables.