Development of a rapid determination of pesticides in coated seeds using a high-performance liquid chromatography-UV...

For the determination of pesticides in coated seeds, this study compared two HPLC-UV methods, using a short column or a conventional column, as well as two extraction procedures, by ultrasonic extraction at room temperature or by pressurized liquid extraction (PLE). The comparison of selected column performances showed that the short column enabled the 3-fold reduction of analysis time (ca. 9 min vs 29 min) and eluent consumption (ca. 6.1 mL vs 20.8 mL) for the separation of five insecticides (bitertanol, fludioxonil, imidacloprid, metalaxyl-M and tefluthrin) and one bird repellent (anthraquinone) without altering peak resolutions. Recovery rates for pressurized liquid extraction at 120 degrees C were similar (between 84% and 102%) to those obtained by ultrasonication. Both methods were then applied for the extraction of loaded seeds. Rates for ultrasonic extraction at room temperature were lower (from 16% to 95%) than those observed for recovery tests, unlike PLE at 120 degrees C which showed good rates, ranging between 82% and 95%, for all the loaded pesticides.