A method for determining pesticide residues in tea

Abstract

The invention provides a method for measuring the pesticide residue amount in tea leaves. The method includes the following steps of 1, sample pre-treatment, wherein after the tea leaves are smashed and dissolved in water, ultrasonic extraction is conducted through an acetonitrile-acetone solution, and extract is obtained after centrifugation is conducted; 2, stirring rod solid-phase extraction, wherein a stirring rod coated with a polymer-graphene coating is immersed in the extract for solid-phase extraction; 3, gas chromatography-mass spectrometry detection. Pesticide residues are triazole pesticide residues. The polymer-graphene coating on the stirring rod is a chitosan-graphene coating. By means of the method, the pesticide residue amount in the tea leaves can be efficiently, easily and conveniently detected.

Description

technical field [0001] The invention belongs to the technical field of analysis and detection, and in particular relates to a method for checking the residual amount of triazole pesticides in tea by using gas chromatography-mass spectrometry. Background technique [0002] Triazole pesticides are organic heterocyclic compounds, which can kill bacteria and regulate plant growth. Some triazole compounds can strongly inhibit the formation of ergosterol in pathogenic bacteria, exhibit a strong bactericidal effect, and have a plant growth regulating effect; some triazole compounds can prevent the formation of auxin and gibberellin in plants, showing strong The plant growth inhibitory effect can control the growth of crops, achieve the effect of disease prevention and lodging resistance, and also has a bactericidal effect. In the mid-1970s, the first triazole fungicide triadimefon came out, creating a new category of fungicides. Because of its high-efficiency, systemic, and broad...

AI Technical Summary

Problems solved by technology

However, its unreasonable use will cause potential health threats to humans and pollute the ecological environment, and its residues in food have attracted more and more attention.

[0003] Due to the low amount of triazole pesticide residues in tea leaves, traditional liquid-liquid extraction or SPE cartridges are usually used for extraction. Various solvents are used in the whole process, and the operation steps are cumbersome, resulting in a large loss of the components to be tested. The extraction efficiency Not high, affecting the final detection precision and accuracy