Study On The Analysis Methods Of Pesticide Residues In Fruits And Vegetables

With the increasing use of the pesticides, more attention is given to residues in vegetables and fruits and their harms on human health and the environment. Therefore, it is important to establish a rapid, simple and efficient method to determine pesticide residues in in vegetables and fruits. In recent years, Liquid chromatography-tandem mass spectrometry for wide usage, high sensitivity and good repeatability has been widely applied for the analysis of pesticides in complex matrix.The paper aimed at positive pesticides in real sample and combined with dispersive solid phase extraction and solid phase extraction to further improve the relevant detection technology.The detail are as follows:1. A method was developed for the simultaneous determination of31residue pesticides in peach by liquid chromatography-tandem mass spectrometry and the pesticide distribution in the peel and pulp of peach was researched.Samples were extracted and cleaned up referred to QuEChERS. Carbendazim, thiophanate-methyl and chlorpyrifos presented the higher positive ratio in the studied pesticides in real sample. According to the distribution ratios between peel and pulp, six available pesticides were suggested to be used in practice.2. A new multi-residue analytical method combined with solid phase extraction was developed for the determination of27carbamate pesticide and their metabolite residues in ginger using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The step of solvent exchange prior to solid phase extraction removed some polar components from acetonitrile extracts, which greatly improved clean-up effect and reduced matrix interferences. The method successfully solved the problem of the detection in the ginger with complex matrix.3.51kinds of pesticides were selected as target compounds to investigate the matrix effect in16kinds of fruit and vegetables and the difference of matrix effect in different brands of tea were also discussed. The methods eliminating and compensating matrix effects in the LC-MS/MS were summarized and applied to actual pesticide analysis, effectively reducing the influence of matrix effects on the results.