大米中28种有机氯及拟除虫菊酯农药残留GC-ECD测定

Determination of 28 kinds of organochlorine and pyrethoid pesticides residues in rice by GC-ECD

利用气相色谱(GC)建立了大米中28种有机氯农药及拟除虫菊酯类农药同时测定的方法。试样中农药残留在超声波振荡条件下用乙腈提取,经佛罗里硅土和PSA净化,GC-电子捕获检测器(ECD)检测。方法的检出限为0.001～0.025mg/kg,回收率为84.5%～104.5%,相对标准偏差为1.1%～6.7%。该方法的灵敏度、准确度和精密度均符合农药残留测定的技术要求。

The method for determing 28 organochlorine and pyrethoid pesticides residues in rice has been build utilizing GC-ECD technique.The pesticide residues in rice samples were extracted with acetonitrile and by ultrasonic,organochlorine pesticides and pyrethoids pesticides were cleaned-up by Florisil and PSA,determined by gas chromatography-electron capture detection（GC-ECD）.The limits of detection were 0.001~0.025mg/kg,the average recoveries for the pesticides ranged from 84.5% to 104.5%,with the relative standard deviation（RSD）between 1.1% and 6.7%.The proposed method was characterized by simplicity,higher sensitivity and accuracy.