Development a HPLC method for simultaneous determination of Azinphose methyl, Diazinon, Phosalone and Chlorpyrifos residues in fruit

A high-performance liquid chromatography with ultraviolet detection (HPLC/UV) methodwhich was used solid-phase extraction for cleanup, was developed for the determination ofAzinphos methyl ,Phosalone, Diazinon and Chlorpyrifos residues in fruits. A full factorialexperimental design was used for development of HPLC condition and evaluation of effect ofthree factors (pH of mobile phase, percent of acetonitril in mobile phase and flow rate) on theretention time and resolution of peaks. The samples were extracted with Hexan/Aceton(50/50)and then is loaded onto a C18 end-caped SPE cartridge for further clean up. For SPE conditionoptimization, several solvents (acetonitril, dichloromethane, ethyl acetate and hexane) weretested as eluent and the best recovery was found with hexane. The optimum HPLC conditionwas achieved with acetonitril: water (60:40) as mobile phase, flow rate 1 ml/min, on C8 column.The standard calibration curves were linear between 0.05-1μg/ml for Azinphos methyl and0.1-2 μg/ml for others. The hexan:acetone extraction followed by the C18 end-cap SPE cleanupprovided recoveries of >70% for all of pesticides and removing the greatest number of samplematrix interferences.