RP-HPLC methods and quechers for detection of insecticides in rice grains

In this study, methods for detection and determination of monocrotophos, deltamethrin, phosphamidon and dichlorvos had been standardized by combination of reverse phase-high performance liquid chromatography (HPLC) with modified QuEChERS method. UV-VIS detection system and the Brownlee Analytical C18 column were used for the quantification of monocrotophos and deltamethrin with an isocratic flow of 1.70 mL min⁻¹ of mobile phase of acetonitrile and water (90: 10, v/v). Phosphamidon and dichlorvos were separated with an isocratic flow of acetonitrile and water (70: 30, v/v). The peaks of monocrotophos and deltamethrin were depicted at retention times of 0.77 min and 3.01 min and the peaks of phosphamidon and dichlorvos were found at 1.11 and 1.39 min, respectively. The recoveries found in the method were above 80% with the evaluated insecticides, when samples were fortified at 0.05, 0.10, 0.25, 0.50 and 1.00 mg kg⁻¹ levels.