Application Of Eutectic Solvent Liquid Phase Microextraction Technology In The Analysis Of Endocrine Disrupting Pesticides

Because of the heavy use of pesticides,the problem of pesticide residues has become more and more serious.Many countries have enacted relevant laws and regulations to limit the use of high-pollution pesticides.Endocrine disrupting pesticide is a kind of exogenous pesticide which interferes with endocrine system.It can interfere with many links of endocrine system of human or other animals and cause abnormal effect for organism.The harm of this pesticide to the health of human and other animals has been paid more and more attention.In order to manage endocrine disrupting pesticides,countries are actively exploring various ways and methods to screen out a part of priority control to limit the use of high toxicity,high residue pesticides,detection and monitoring of various environmental matrix residues,In the process of detection and monitoring,the traditional sample pretreatment technology is cumbersome,time-consuming and requires a large number of samples and organic solvents,which leads to environmental pollution and endangers the health of the experimenter.At present,sample pretreatment methods are developing in simple,time-saving,miniaturized and less organic solvent use.As a green solvent,deep eutectic solvent has attracted more and more attention in the field of analysis due to its unique physical and chemical properties.As a new separation and preconcentration technique,disperse liquid phase microextraction?DLME?has attracted much attention because of its high enrichment ratio,short extraction time,simple operation,economical and convenient combination.Therefore,it is of great theoretical and practical significance to study the application of deep-eutectic solvent-dispersed liquid-phase microextraction technique in the analysis of endocrine disturbance pesticide residues.A high performance liquid Chromatography method for the determination of five fungicides?triazol,pyrimidine,triadimefon,enazolol and pyrimidine?by liquid Phase Microextraction with deep eutectic solvent in this study.Phenol was used as hydrogen bond donor.Choline chloride is a low-melting solvent composed of hydrogen bond receptors as extraction solvent and THF as dispersant to form turbid droplets.The target analyte is extracted into a small amount of DESs phase.After centrifugation,the DESs phase is absorbed into high performance liquid chromatography?HPLC?.The important factors affecting the extraction efficiency were selected and optimized.The results showed that the optimum extraction conditions were as follows:the molar ratio of choline chloride to phenol was 1:2 ratio is the best,and at the optimum extraction conditions(sample volume 5 mL,DES_2.That is,the ratio of choline chloride to phenol is 1:2 was 150?L,THF was 150?L)The recovery time was tested under ultrasonic time of 20 min and centrifuge time of 10 min.The recoveries ranged from 73.7 to 102.3%,the relative standard deviation?RSD?was 0.7-7.1%,and the minimum detection limit?LOD?was 0.026⁰.052?g/L,The limit of quantification is 0.09?g/L⁰.17?g/L.A high performance liquid chromatography?HPLC?method for the determination of pesticide residues in seven herbicides?simazine,azinone,atrazine,dimethuron,atrazine,rigoprol,ethoxyfuroxime yellow?by liquid phase microextraction with deep eutectic solvent was established.Using n-decanoic acid as hydrogen bond donor and tetrabutylammonium chloride as hydrogen bond acceptor,the low-melting solvent was used as extraction solvent and mixed with the extracted sample form turbid droplets.The target analyte is extracted into a trace amount of DESs phase,and subjected to centrifugation to extract DESs into high performance liquid chromatography for analysis.Select and optimize important factors affecting extraction efficiency.Studies have shown that the low eutectic solvent formed by the ratio of n-decanoic acid to tetrabutylammonium chloride in 3:1 has the best extraction efficiency.At the same time,under the optimal extraction conditions(sample capacity is 5mL,the amount of DESs added is Addition recovery experiment was carried out under 120?L,ultrasonic time of 10 min and centrifuge time of 10 min.The recovery was between 79.3 and 98.2%,and the relative standard deviation?RSD?was 0.9 to 4.7%.The minimum detection limit?LOD?0.026?g/L⁰.057?g/L,The limit of quantification is 0.09?g/L⁰.19?g/L.In this study,DESs was used as extractant in disperse liquid phase microextraction to provide safe and reliable extraction and separation technical support for endocrine disrupting pesticide residue analysis.Reduce the harm to the environment and human health caused by the use of organic solvents.