A Novel Method for Determination of Topramezone Residues in Maize

A simple and inexpensive method was developed using solid-phase extraction, together with high performance liquid chromatographic method with UV detection for determination of topramezone residues in maize. The evaluated parameters include the extracts by phenyl solid phase extraction cartridge using methanol, distilled water and tetrahydrofuran solvents. The method was validated using maize samples spiked with topramezone at different fortification levels (0.01 and 0.1 μg/g). Average recoveries (using each concentration six replicates) ranged 85-95%, with relative standard deviations less than 2%, calibration solutions concentration in the range 0.0110.0 μg/mL and limit of detection (LOD) and limit of quantification (LOQ) were 0.003μg/g and 0.01μg/g respectively. Finally the maize and soil residue samples were re analyzed by HPLC.