Study On Determanation Of Multi-Pesticide Residues Using Gas Chromatography Mass Spectrometry And Gel Permeation Chromatography

With the rising of peoples'living standards, the question of food safety has attracted more and more attention. Due to large-scale use of pesticides, pesticide residues in food and environment has attracted extensive attention,which also became the technical trade barriers in China's merchandise exports. According to the kinds of pesticides used and the limits for pesticide residues in fugu, eel, prawn samples, this paper studied extraction, purification of sample pretreatments and GC-MS detection conditions of pesticide residues and also developed a new analytical procedure to determine 191 multiple pesticide residues in fugu, eel, prawn and other fishes in water. The details are as follows:1. Building the simple, effective sample pretreatments. Using the ethyl acetate–cyclohexane(1:1,v:v) extracting residual pesticides in samples,and using the same solvent as the gel permeation chromatography mobile phase can remove macromolecule impurities such as proteins, lipids in sample efficiently, then extracting and concentrating the residual pesticides in samples on line,meanwhile investigating the 173 pesticides'gel permeation chromatography action parameters.2. In this research, we established the GC-MS detection method for 191 pesticides. Linear regression in the corresponding concentration range was all over 0.97. The limits of detection and the limits of quantification were 0.002~0.3 mg/kg, 0.007~1.2 mg/kg respectively.3. We took the precision and accuracy methodology test and got satisfied conclusion. The recovery was conducted at two spiked levels which is the LOQ concentration and 4 times of LOQ concentration, the validation results were as follows: the overall recoveries were from 50.2% to 120% (89.5% of the recoveries were from 70% to 120%), with the relative standard deviations (RSDS) of 0.6%-21.6%.