Gas chromatography/positive-ion chemical ionization mass spectrometry

Prison, G.,Tedeschi, L, Maietti, S. and Ferrara, S.D. (1998). Determination of gamma-hydroxybutyric Acid (GHB) in plasma and urine by headspace solid-phase microextraction (SPME) and gas chromatography-positive ion chemical ionization-mass spectrometry. In Proceedings of the 1998 Joint Society of Forensic Toxicologists and the International Association of Forensic Toxicologists SOFT/TIAFT International Meeting, Spiehler, V. (Ed.), pp. 394 404. 

GAS CHROMATOGRAPHY/POSITIVE-ION CHEMICAL IONIZATION MASS SPECTROMETRY... 

Structural information about toxaphene components can be obtained by gas chromatography coupled to electron ionization mass spectrometry (GC/EI-MS), positive ion chemical ionization mass spectrometry (GC/PICI-MS) or negative ion chemical ionization MS(GC/NICI-MS). Mass separation is performed by low resolution quadrupole or high resolution magnetic field instruments, by ion trap systems (GC/IT-MS), or by tandem mass spectrometry (MS/MS) offering a broad spectrum of possibihties. 

Bergh C, Torgrip R, Ostman C (2010) Simultaneous selective detection of organophosphate and phthalate esters using gas chromatography with positive ion chemical ionization tandem mass spectrometry and its application to indoor air and dust. Rapid Commun Mass Spectrom... 

In order to determine ureas and metabolites of triazines and ureas in agricultural soils, reverse-phase liquid chromatography was used with atmospheric pressure chemical ionization/mass spectrometry (APCI/MS), in positive mode. Gas chromatography/ion trap mass spectrometry was used in MS/MS mode to analyze the parent compounds of the triazines and chloroacetanilides. Method performance was much better in GC-MS/MS than in LC-MS, and acetochlor LOQ was dramatically improved by using GC-MS/MS, this herbicide being very poorly ionized into the APCI interface. 

Gas chromatography-mass spectrometry of nine nltroaromatic compounds was carried out in order to evaluate its potential as an analytical method for the determination of TNT and possible related impurities in environmental samples such as water and soil [8]. Nitrobenzene, the three mononitrotoluenes (MNTs), 1,3-DNB, 2,4-DNT, 2,6-DNT, and TNB were analyzed in addition to TNT. The MS ionization techniques included El, positive-ion chemical ionization (Cl) and negative-ion Cl (NCI), all recorded in both full-scan and selective ion monitoring (SIM) modes. They were compared with GC analysis with electron capture detection (ECD). The comparison included sensitivity (detection limits), linear response range, and precision. The GC ECD was recommended for those analyses where there was no uncertainty in the identity of the analytes. 

Durand, G. and Barcelo, D., Confirmation of chlorotriazine pesticides, their degradation products and organophosphorus pesticides in soil samples using gas chromatography-mass spectrometry with electron impact and positive- and negative-ion chemical ionization. Anal. Chim. Acta, 24, 259-271, 1991. 

Bruins, A. P., 1987. Gas chromatography-mass spectrometry of essential oils. Part II Positive ion and negative ion chemical ionization techniques. In Capillary Gas Chromatography in Essential Oil Analysis, P. Sandra and C. Bicchi (eds.), pp. 329-357. Heidelberg, Germany Dr. A. Huethig Verlag. 

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