Gas chromatographic determination of pesticides in vegetable samples by sequential positive and negative chemical ionization and tandem mass spectrometric fragmentation using an ion trap analyser

Citation
Md. Hernando et al., Gas chromatographic determination of pesticides in vegetable samples by sequential positive and negative chemical ionization and tandem mass spectrometric fragmentation using an ion trap analyser, ANALYST, 126(1), 2001, pp. 46-51
Citations number
11
Categorie Soggetti
Chemistry & Analysis","Spectroscopy /Instrumentation/Analytical Sciences
Journal title
ANALYST
ISSN journal
00032654 → ACNP
Volume
126
Issue
1
Year of publication
2001
Pages
46 - 51
Database
ISI
SICI code
0003-2654(2001)126:1<46:GCDOPI>2.0.ZU;2-F
Abstract
A selective and sensitive chromatographic method is described for the deter mination of nine organochlorine and organophosphorus pesticides in vegetabl e samples by gas chromatography-mass spectrometry. The proposed method comb ines the use of positive and negative chemical ionisation and tandem mass s pectrometric fragmentation, resulting in a significant increase in selectiv ity and allowing the simultaneous confirmation and quantification of trace levels of pesticides in complex vegetable matrices. Parameters relative to ionisation and fragmentation processes were optimised to obtain maximum sen sitivity. Repeatability and reproducibility studies yielded relative standa rd deviations lower than 25% in all cases. Identification criteria, such as retention time and relative abundance of characteristic product ions, were also evaluated in order to guarantee the correct identification of the tar get compounds. The method was applied to real vegetable samples to demonstr ate its use in routine analysis.