Minimizing geometric isomerization of α-cypermethrin in the residue analysis. (1st April 2016)

• Record Type: Journal Article
• Authors: Liu, Xueke; Shen, Zhigang; Wang, Peng; Liu, Chang; Yao, Guojun; He, Jiayuan; Liu, Donghui; Zhou, Zhiqiang
• Is Part Of: Food chemistry. Volume 196(2016)
• Page Start: 828
• Page End: 832
• Publication Date: 2016-04-01
• Subjects: α-Cypermethrin -- Isomerization -- Animal foods -- GC–ECD; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2015.09.059
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: The method can obviously reduce the isomerization of α-cypermethrin. The method can simultaneously analyze α-cypermethrin and the main acid metabolites in animal foods. Taguchi orthogonal experiment was used to optimize the derivatization factors. The method was used to analyze four animal foods (chicken, honey, milk and pork). Abstract: Isomerization of chiral pesticides in residue analysis has not drawn much attention which can cause wrong decisions on the enantioselective environmental behavior. A residue analysis method for α-cypermethrin and its three acid metabolites, cis/trans-3-(2, 2-dichlorovinyl)-2, 2-dimethyl cyclopropanecarboxylic acid (cis/trans-DCVA) and 3-phenoxybenzoic acid (3-PBA), in foods such as chicken, honey, milk and pork has been established, in which the isomerization of α-cypermethrin was minimized. The target compounds were determined by GC–ECD after a derivatization reaction with 1, 1, 1, 3, 3, 3-hexafluoroisopropanol. The conditions of the method were optimized by Taguchi orthogonal experiment. Under the optimized conditions, good linearity was obtained with correlation coefficients ranging from 0.9964 to 0.9998. The limits of detection were 0.001–0.005 mg kg −1 . The recoveries were 70.9–114.9% with relative standard deviations of 0.6–15%. In addition, ratios of isomerization ranged only from 2.3% to 7.0%. This method was applied in commercial animal food products.