Method for analyzing and determining spirodiclofen residues in tea leaves and tea soup

Abstract

The invention discloses a method for analyzing and determining spirodiclofen residues in tea leaves and tea soup, and belongs to the technical field of tea leaf acaricide residue detection. The method comprises the following steps: 1) preparing a fresh tea leaf and green tea / black tea sample: soaking in 1% formic acid water, adding 1-5% formic acid acetonitrile or acetic acid acetonitrile for extraction, adding NaCl, centrifuging, taking out supernate, adding 1-5% formic acid acetonitrile or acetic acid acetonitrile into residues, repeatedly extracting, mixing the supernates, concentrating to be dry, re-dissolving with formic acid acetonitrile, transferring into a centrifuge tube filled with C18, GCB and MgSO4, purifying and centrifuging, separating the supernate, concentrating to be dry, and performing constant volume with acetonitrile; 2) preparing a tea soup sample: adding 1-5% formic acid acetonitrile or acetic acid acetonitrile into the tea soup, uniformly mixing, adding NaCl, centrifuging, taking out supernate, repeatedly extracting a lower layer, mixing the supernates, concentrating to be dry, and using acetonitrile for fixing the volume; and 3) detecting through an ultra-high performance liquid chromatography-mass spectrometry matrix external standard method. The method meets the residue analysis requirement and can meet the requirement for detection of spirodiclofen residues in the tea leaves and the tea soup.

Description

technical field [0001] The invention belongs to the technical field of detection of acaricide residues in tea leaves, and in particular relates to a method for analyzing and measuring spirodiclofen residues in tea leaves and tea soup. Background technique [0002] Spirodiclofen (Spirodiclofen, C 21 h 24 Cl 2 o 4 , CAS N O . 148477-71-8, chemical structure see figure 1 ), the trade name is Mite Danger, which is a highly efficient and low-toxic non-systemic acaricide with a novel chemical structure of tetronic acid developed by Bayer Crop Science Company of Germany and applied for a patent in 1993. Its mechanism of action is by inhibiting The fat synthesis in the body of harmful mites destroys the energy metabolism activities of harmful mites, and finally kills harmful mites. It is mainly used to control harmful mites on citrus plants, grapes, pome fruit, stone fruits, nuts and other plants. At present, spirodiclofen has been registered and listed in nearly 50 countries ...

AI Technical Summary

Problems solved by technology

However, at present, there is no method report specifically for the residue analysis of spirodiclofen in tea and tea soup at home and abroad.

Although the prior art discloses the residual analysis of spirodiclofen in citrus and soil, etc., it also uses liquid chromatography mass spectrometry detection, but the conditions are different, and the difference from this application is that this application has carried out pretreatment optimization and liquid phase mass spectrometry conditions Improved, involving more complex sample handling matrices

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