Analysis Of Pesticide Residue In Fruit And Vegetable With Gel Permeation Chromatography

An analytical technique of four type of pesticide, about 40 kinds of pesticides (organophosphorus, organochlorine, pyrethroid and carbamate) has been studied in fruits and vegetables. Samples were extracted with proper organic solvents, purified by GPC in order to remove some polymers molecular like pigments, carbohydrate, wax esters and then determined by GC and HPLC.For the determination of organophosphorus pesticide residues by gas chromatography with gel permeation chromatography purification, ethyl acetate was used as the extract solvent. The cut-off time was selected in accordance with the elution curve of blank sample and the standards elution profile by GPC purification. Recoveries were from 69.3%～107.1%, the relative standard deviations from0.3%～7.9%. The lowest detection limit was 0.0025～0.0073mg/kg. The method showed good effect in residue analysis.For the determination of organochlorine and pyrethroid pesticide residues, the sample was extract with petroleum ether. The recoveries were from 69.9%～127.6%, the relative standard deviations from1.0%～14.6%. The lowest detection limit was 0.00011 0.0018mg/kg. The result showed that the method is easy fast, sensitive and good purification effect.For the determination of five carbamate pesticide residues by high performance liquid chromatography with gel permeation chromatography purification, sample was extracted with acetonitrile and purified with gel permeation chromatography. Methanol-water was used as the mobile phase by gradient elution, flow rate of 1.0mL/min, using a fluorescence detector and quantitating with external standard method. Carbamate residues showed good linearity, recoveries were from 69.1%～108.7%, with relative standard deviations from 2.0%～9.2%, The lowest detection limit was 0.001～0.009mg/kg.