title: Development and Validation of an HPLC Method for Determination of Thiamethoxam and Its Metabolites in Cotton Leaves and Soil.
abstract: An easy and simple analytical method was standardized and validated for the estimation of residues of thiamethoxam and its metabolites in cotton. The samples were extracted with acetonitrile, water, and methanol; diluted with brine solution; partitioned into dichloromethane and ethyl acetate; dried over anhydrous sodium sulfate; and cleaned up by glass column chromatography. Final clear extracts were concentrated under vacuum and reconstituted into HPLC grade acetonitrile, and residues were estimated using an HPLC instrument equipped with a C18 column and photodiode array detector system. Acetonitrile-1% formic acid in HPLC grade water (30 + 70) was used as mobile phase at 0.2 mL/min. Consistent recoveries ranging from 82 to 97% for thiamethoxam and its metabolites were observed when samples were spiked at 0.05-1.0 mg/kg levels. The LOQ of the method was determined to be 0.05 mg/kg. The analytical method was validated in terms of the selectivity, linearity, precision, and accuracy of the detection system.
authors.affiliation: Punjab Agricultural University, Department of Entomology, Pesticide Residue Analysis Laboratory, Ludhiana 141004, Punjab, India.
authors.forename: Gagan
authors.initials: G
authors.lastname: Jyot
authors.affiliation: Punjab Agricultural University, Department of Entomology, Pesticide Residue Analysis Laboratory, Ludhiana 141004, Punjab, India.
authors.forename: Balwinder
authors.initials: B
authors.lastname: Singh
mesh_terms: D002851:Chromatography, High Pressure Liquid; D003368:Gossypium / Q000737:chemistry*; D000073943:Neonicotinoids / Q000032:analysis*; D009574:Nitro Compounds / Q000032:analysis*; D010078:Oxazines / Q000032:analysis*; D018515:Plant Leaves / Q000737:chemistry*; D012987:Soil / Q000737:chemistry*; D000077922:Thiamethoxam; D013844:Thiazoles / Q000032:analysis*
chemical_list: D000073943:Neonicotinoids; D009574:Nitro Compounds; D010078:Oxazines; D012987:Soil; D013844:Thiazoles; D000077922:Thiamethoxam