气相色谱法同时测定小麦粉中35种有机磷农药残留量

Simultaneous determination of 35 organophosphorus pesticide residues in wheat flour by gas chromatography

目的建立气相色谱-火焰光度检测器法(GC-FPD)测定小麦粉中有机磷残留量的方法。方法小麦粉样品经过乙腈超声辅助提取后,加入氯化钠盐析,取上清液过膜,利用气相色谱火焰光度检测器进行检测。结果 35种有机磷类农药在0.010~0.200 mg/L浓度范围内呈现良好线性关系,R2】0.99;在0.200、0.100、0.040、0.020、0.010 mg/L的添加水平,小麦粉中35种有机磷类农药平均回收率均在70.80%~115.43%之间,各目标分析物的相对标准偏差(RSD)均小于10%。检出限是0.004~0.010 mg/kg。结论该方法一次性可检测35种有机磷类农药,前处理操作快速简单、效率高、重复性好且灵敏度高。

ABSTRACT:Objective To develop a method for the simultaneous determination of organic phosphorus pesticide residues in wheat flour by gas chromatography with flame photometric detector (GC-FPD).Methods Wheat flour samples were extracted with acetonitrile assisted by ultra-sonic, and the extracts were filtered by microporous membrane, then they were detected by GC-FPD.ResultsThe method showed a good linearity in the range of 0.010~0.200 mg/L for 35 organophosphorus pesticides withR2>0.99. The recoveries were 70.80%~115.43% at 3 spiked levels of 0.200, 0.100, 0.040, 0.020, and 0.010 mg/L for 35 organophosphorus pesticide,and the relative standard deviations (RSDs) were less than 10%. The limits of detections were in the range of 0.004~0.010 mg/kg.ConclusionThis method is suitable for fast, simple, and high sensitive detection of 35 organophosphorus pesticide residues simultaneously.