Determination of 10 pyrethroids residues in Penaeus vannamei by gas chromatography

The method for determination of 10 pyrethroids residues such as tefluthrin in Penaeus vannamei by gas chromatography with electron capture detection(GC-ECD) was developed.Pyrethroids were extracted with hexan-ethylacetate-actone organic solvent and lipids were removed with petroleum ether saturated with acetonitrile.After purification by Florisil column,10 pyrethroids residues were detected simultaneously by GC-ECD.The results indicated that the working curves were linear(r≥0.999 51) in the range of 1-100 ng/mL for 10 pyrethroids.When spiked with 2 μg/kg,10 μg/kg and 20 μg/kg of pyrethroids(1 μg/kg,5 μg/kg and 10 μg/kg for tefluthrin) in Penaeus vannamei blank sample,the average recoveries were 78.0%-110.0% and the intra-day RSD(n=6) were 4.0%-12.0% and the inter-day RSD(n=3) were 2.3%-12.0%.The detection limit as estimated by 10 times signal to noise method for tefluthrin was 1.0 μg/kg and that for bifenthrin,fenpropanate,cyhalothrin,pemethrin,cyfluthrin,cypermethrin,tau-fluvalinate,fenvalate,deltamethrin was 2.0 μg/kg respectively.This method can detect pyrethroids residues in aquatic product quickly and exactly.