GC Determination of Organophosphorous Pesticides in Potato with Ultrasonic Extraction and Dynamic Liquid Phase Micro-extraction

Smashed potato sample was extracted ultrasonically with water,the filtrate was treated by dynamic liquid phase micro-extraction(DLPME) using n-octanol as extracting agent,to separate and enrich the 3 organophosphorus pesticides,i.e.,dichloroas,methylparathion and parathion,which were then determined by GC.OV-1701 capillary column was used in GC separation and flame photometric detection was adopted in the determination.Ranges of linearity for the 3 organophosphorous pesticides were same between 2.0-50.0 μg·g-1,with values of detection limit(3S/N) of 0.20,0.46,0.42 μg·g-1 for methylparathion,parathion and dichlorovos respectively.Using potato samples as matrixes,values of recovery found by standard addition method were in the range of 90.6%-101% with RSD′s(n=7) in the range of 3.2%-5.6%.