QUANTIFICATION OF PINOXADEN HERBICIDE IN WHEAT GRAINS AND VEGETABLE SAMPLES BY ULTRASONICATIONASSISTED EXTRACTION AND HIGH- PERFORMANCE LIQUID CHROMATOGRAPHY

A method for high-performance liquid chromatographic (HPLC) for the residue determination of Pinoxaden in food samples was developed and validated. The chromatographic analysis was carried out by HPLC, on a C18 packed capillary column with temperature gradient, 20μl injection volume and ultraviolet detector at 280 nm. Wheat potato and cabbage samples were collected from fields near agricultural forms in Peshawar where the herbicide pinoxaden was not sprayed. Samples were spiked with amount between 5-and 15μg g^-1 of herbicide and were isolated from samples by applying ultrasonication extraction at ambient temperature. Percent recoveries were improved by optimizing solvent types, solvent volume, and time. Calibration curve range determined by HPLC was 0.2-40μgmL-1. Application of this procedure to the analysis of herbicide in ester and acid form showed the effectiveness of the methodology proposed.