The Determination Of Acephate And Dimethoate In Apple And Banana By On-line Single Drop Microextraction(SDME) And HPLC Coupled With TOF Mass Spectrometry

Pesticides are extensively used for the control of diseases,weeds,and pests of cultivated plants in the whole world.Consumers thus worry more about the safety and chemical impurities in food and environments in the past decades.As result,more bans and regulations have imposed in various domestic and international laws.Current trends in analytical chemistry are aimed at facilitation and miniaturization of sample preparation,and also to decrease organic solvents use.Therefore,many micro extraction techniques have been developed in order to simplify the analysis step,to increase the sample rate,and to improve the quality and sensitivity of analytical methods.One emerging technology is single droplet micro-extraction which is widely used for pesticides determinations in fruits.A direct immersion single-drop micro extraction(DI-SDME)method was developed to evaluate the contents of acephate and dimethoate in bananas and apples using liquid chromatography coupled with mass spectrometry.Extraction parameters,including stirring rate,ionic strength,pH,position of organic solvent droplet in the sample,have been fully optimized.The optimal DI-SDME was applied in the determination of the acephate and dimethoate contents with30 min extraction,4 ?l chloroform,30? temperature,and 138 rpm stirring speed.The best linearity,accuracy,detection limits and sensitivity were obtained with this method for the two pesticides studied.We speculate that this method suitable and up-to-date work can significantly improve the detection of both pesticides in fruits and contribute to an enhanced understanding of their contents that will lead to an enhancement of their use.