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

Abstract

A high-performance liquid chromatography with ultraviolet detection (HPLC/UV) method<br />which was used solid-phase extraction for cleanup, was developed for the determination of<br />Azinphos methyl ,Phosalone, Diazinon and Chlorpyrifos residues in fruits. A full factorial<br />experimental design was used for development of HPLC condition and evaluation of effect of<br />three factors (pH of mobile phase, percent of acetonitril in mobile phase and flow rate) on the<br />retention time and resolution of peaks. The samples were extracted with Hexan/Aceton(50/50)<br />and then is loaded onto a C18 end-caped SPE cartridge for further clean up. For SPE condition<br />optimization, several solvents (acetonitril, dichloromethane, ethyl acetate and hexane) were<br />tested as eluent and the best recovery was found with hexane. The optimum HPLC condition<br />was achieved with acetonitril: water (60:40) as mobile phase, flow rate 1 ml/min, on C8 column.<br />The standard calibration curves were linear between 0.05-1μg/ml for Azinphos methyl and<br />0.1-2 μg/ml for others. The hexan:acetone extraction followed by the C18 end-cap SPE cleanup<br />provided recoveries of >70% for all of pesticides and removing the greatest number of sample<br />matrix interferences.