Determination of diazinon and ethion residues in samples of rice by using dispersive solid-phase extraction with gas chromatography

In the present study, a solid phase micro extraction /gas chromatography-flame ionization detection using TAGUCHI software was investigated for extraction and simultaneous measurement of two organophosphorus pesticides (Diazinon and Ethion) residues in rice samples. This technique by using magnetic iron nanoparticles coated with chitosan was used as a rapid, sensitive and inexpensive method for easy and quick separation. Iron oxide nanoparticles, were synthesized by co-precipitation method and coated with chitosan [1-3]. The effects of the extraction parameters, including; pH, speed and time of extraction, the amount of nanoparticles, speed and time of desorption on the extraction efficiency were studied and optimized. The calibration graphs were linear in the range about of 0.007-0.01mg/Land limits of detection 0.0002 mg/L for Diazinon and Ethion. The proposed procedure was applied effectively to determine residues selected analytes in rice samples.