Determination of Thiamethoxam Residues in Tomato by High Performance Liquid Chromatography with UV Detection

A simple and novel analysis method to detect thiamethoxam residues in tomato was developed using solid phase extraction coupled with high performance liquid chromatography with ultraviolet detection. The pesticide residues present in matrix were extracted with acetonitrile and purified by Pesticarb/NH2 solid phase extraction cartridge. Mean recoveries for the analyte at the levels of 0.01, 0.05 and 0.10 mg kg(-1) ranged from 83 to 85 % with relative standard deviations less than 7.5 % and limit of quantification was 0.01 mg kg(-1). This method has been applied to analyze thiamethoxam in real samples of tomato. The half-life of thiamethoxam in tomato was 4.6 days and the residues in tomato m ere below the maximum residue limit of European union (0.1 mg kg(-1)) after one day.