Method for simultaneously measuring multiple residues of organic chloride and pyrethroid pesticides

Abstract

The invention discloses a method for simultaneously measuring multiple residues of organic chloride and pyrethroid pesticides. The method comprises the following working procedures: crushing a tobacco sample until grain diameters are less than 450 mu m; adding 10 to 20ml of extracting solution and internal standard solution into every program of tobacco sample; extracting the mixed solution by using ultrasonic wave; filtering the mixed solution by using a funnel filled with anhydrous sodium sulfate to obtain the extracting solution; adding the extracting solution into a Florisil solid extraction column for extracting and eluting; collecting an eluent; analyzing the eluent by using a gas chromatograph, wherein the analysis comprises the following conditions: adopting an Elite 5MS capillary column, high-purity N2 as a carrier gas, a constant flow mode in which the flow rate is 0.5 to 1.5 ml / min, a sample inlet temperature of between 280 and 320 DEG C, a detector temperature of between 330 and 370 DEG C, splitless sampling in which the sampling volume is between 1 and 2 mu L, and an initial temperature of 100 DEG C which rises from 100 to 180 DEG C at a speed of 8 DEG C / min, is kept for 4 minutes, rises from 180 to 270 DEG C at the speed of 5 DEG C / min and is kept for 15 minutes until all sample flows out completely; and determining the nature of the sample by using the retaining time of a standard sample and quantifying by using an internal standard method. In the method, ultrasonic wave is adopted for extracting and a solid extraction column is adopted for purifying, so that the method has the advantages of operating step simplification, high work efficiency, good purification effect, capability of simultaneously measuring multiple residues of 25 kinds of pesticides including 17 organic chloride pesticides of hexachlorocyclohexane, DDT and the like, seven pyrethroid pesticides such as fenpropathrin and the like, and one plant growth regulator.

Description

technical field

[0001] The invention belongs to the technical field of pesticide residue analysis, in particular to a method for simultaneously measuring multiple residues of organochlorine and pyrethroid pesticides. Background technique

[0002] Although organochlorine insecticides have not been recommended or prohibited to be used on tobacco, and some pyrethroid insecticides are being recommended for use, but organochlorine and pyrethroid insecticide residues are still a major issue in tobacco and tobacco at home and abroad. Tobacco pesticide residues of concern in tobacco products. Therefore, standardized methods have been established for these two types of pesticide residues at home and abroad. For example, the methods for the analysis of organochlorine pesticide residues in tobacco and tobacco products include "GB / T13596-2004 Determination of Organochlorine Pesticide Residues in Tobacco and Tobacco Products Chromatography", the analysis methods of pyrethroid insecticid...

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