Determination of 17 pyrethroid residues in troublesome matrices by gas chromatography/mass spectrometry with negative chemical ionization

• Published in: Talanta (Oxford) Vol. 84; no. 1; pp. 141 - 147
• Main Authors: Shen, Chong-yu, Cao, Xiao-wen, Shen, Wei-jian, Jiang, Yuan, Zhao, Zeng-yun, Wu, Bin, Yu, Ke-yao, Liu, Han, Lian, Hong-zhen
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.03.2011; Elsevier
• Subjects: Analytical chemistry; Chemistry; Chromatographic methods and physical methods associated with chromatography; Cleaning; Exact sciences and technology; Food Analysis - economics; Food Analysis - methods; Food Contamination - analysis; Gas chromatographic methods; Gas Chromatography-Mass Spectrometry - economics; Gas Chromatography-Mass Spectrometry - methods; Gas chromatography/mass spectrometry; Ionization; Isomerization; Limit of Detection; Linear Models; Mass spectrometry; Mathematical analysis; Matrices; Matrix methods; Negative chemical ionization; Onions; Pesticide Residues - analysis; Pesticide Residues - chemistry; Pyrethrins - analysis; Pyrethrins - chemistry; Pyrethroids; QuEChERS; Reproducibility of Results; Residues; Spectrometric and optical methods; Time Factors; Troublesome matrices; Vegetables - chemistry; Pyrethroids; Negative chemical ionization; Troublesome matrices; Gas chromatography/mass spectrometry; Isomerization; QuEChERS; Chemical analysis; Internal standard; Sample preparation; Detection limit; Hexane; Standard deviation; Monitoring; Quantitative analysis; Interference; Pesticides; Secondary ion mass spectrometry; Chemical ionization; Gas chromatography; Residue; Acetonitrile; Analytical method; Negative ion; Yield; Technique; Mass spectrometry
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2010.12.041

An analytical method with the technique of QuEChERS (quick, easy, cheap, effective, rugged and safe) and gas chromatography (GC)/mass spectrometry (MS) in negative chemical ionization (NCI) has been developed for the determination of 17 pyrethroid pesticide residues in troublesome matrices, including garlic, onion, spring onion and chili. Pyrethroid residues were extracted with acidified acetonitrile saturated by hexane. After a modified QuEChERS clean-up step, the extract was analyzed by GC-NCI/MS in selected ion monitoring (SIM) mode. An isotope internal standard of trans-cypermethrin-D 6 was employed for quantitation. Chromatograms of pyrethroids obtained in all these matrices were relatively clean and without obvious interference. The limits of detection (LODs) ranged from 0.02 to 6 μg kg −1 and recovery yields were from 54.0% to 129.8% at three spiked levels (20, 40 and 60 μg kg −1 for chili, and 10, 20 and 30 μg kg −1 for others) in four different matrices depending on the compounds determined. The relative standard deviations (RSDs) were all below 14%. Isomerization enhancement of pyrethroids in chili extract was observed and preliminarily explained, especially for acrinathrin and deltamethrin.