Capillary gas chromatography/atmospheric pressure negative chemical ionization mass spectrometry of the 22 isomeric tetrachlorodibenzo-p-dioxins

Mitchum, R. K.; Korfmacher, Walter A.; Moler, G. F.; Stalling, David L.

doi:10.1021/ac00241a028

Cited by 60 publications

(33 citation statements)

References 54 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This statement is based on both methods ionizing compounds by the mechanisms of EC, dissociative EC, proton abstraction, and halide adduction, and led to the conclusion that these techniques ionize a wider array of compounds than Ni-APCI. However, several studies of Ni-APCI have shown this method to have excellent sensitivity, especially for compounds with positive electron affinity (EA) [5,12,13]. Early work with APCI was primarily carried out using gas chromatographic introduction and, thus, the ion source was solvent free [13][14][15][16][17].…”

Section: Resultsmentioning

confidence: 99%

Ionization mechanisms related to negative Ion APPI, APCI, and DART

McEwen

Larsen

2009

J. Am. Soc. Mass Spectrom.

View full text Add to dashboard Cite

A recent report found that negative ion atmospheric pressure photoionization (Ni-APPI) and direct analysis in real time (Ni-DART) ionize compounds by electron capture, dissociative electron capture, proton abstraction, and anion adduction. The authors of this report suggested that the common ionization of Ni-APPI and Ni-DART demonstrated that these techniques ionize a wider array of compounds than negative ion atmospheric pressure chemical ionization (Ni-APCI). Here we show that Ni-APCI, using the atmospheric sample analysis probe (ASAP) technique, in the absence of solvent vapors, ionizes the same and similar compounds by the same reported mechanisms. These results are supported by previous publications, which show that each mechanism is active for Ni-APCI. This work demonstrates that irrespective of the initial method of ionization, at atmospheric pressure, similar ion/ electron-molecule chemistries prevail. (J Am Soc Mass Spectrom 2009, 20, 1518 -1521

show abstract

Section: Resultsmentioning

confidence: 99%

Ionization mechanisms related to negative Ion APPI, APCI, and DART

McEwen

Larsen

2009

J. Am. Soc. Mass Spectrom.

View full text Add to dashboard Cite

show abstract

“…The detection limits for 2,3,7,8-TCDD/F in the SIM mode were 0.5 pg for the 2,3,7,8-TCDF standard (Clement & Tosine, 1988) and 14-40 pg in deionized water . PCBs, chlorinated methoxybiphenyls, and some organochlorine pesticides did not interfere; therefore that method had an important advantage (Mitchum et al, 1982). According to a study (Revelsky et al, 1992), the detection limit of 2,3,7,8-TCDD in aqueous samples in the SIM mode (m/z 176) was 10 pg.…”

Section: B Sensitive Detection: Negative Chemical Ionization With DImentioning

confidence: 99%

“…It was stated (Mitchum et al, 1982) that for all 2:2-substituted TCDDs, excluding 1,3,7,8-and 2,3,7,8-, and for all 1:3-substituted TCDDs, excluding 1,2,4,6-and 1,2,4,9-, the formation of the M À ion is characteristic for the APCI mode with oxygen as reagent gas. In the TCDF spectra, Cl À and [M-Cl þ O] À were the major ion peaks, and the molecular ions were not observed under APCI conditions (Clement & Tosine, 1988).…”

Section: B Sensitive Detection: Negative Chemical Ionization With DImentioning

confidence: 99%

Determination of polychlorinated dibenzo‐p‐dioxins, dibenzofurans, and biphenyls by gas chromatography/mass spectrometry in the negative chemical ionization mode with different reagent gases

Chernetsova

Revelsky

et al. 2002

Mass Spectrometry Reviews

View full text Add to dashboard Cite

Reagent gases that are used in mass spectrometry in the NCI mode for the determination of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) are discussed. Ion-molecule reactions and respective characteristic ions that form while using reagent gases (CH(4), O(2), i-C(4)H(10), NH(3), H(2), He, Ar, Xe, SF(6)) or gas mixtures (CH(4)/O(2), Ar/CH(4), CH(4)/H(2)O, Ar/O(2), i-C(4)H(10)/CH(2)Cl(2)/O(2)) are reviewed. It is shown that only CH(4), O(2), CH(4)/O(2), and CH(4)/N(2)O are widely used and well studied, even though-in the case of these reagent gases-there are contradictions between the publications of various authors. Such reagent gases as NH(3) and He are not well studied, but further investigations of their use for the determination of organochlorine pollutants could be of interest. The possibilities of more sensitive and selective determination of PCDDs, PCDFs, and PCBs are discussed.

show abstract

“…Recently, several other modes of mass spectrometry involving chemical ionization with reagent gases such as methane, oxygen-doped methane, and isobutane have been used to improve sensitivity and in some cases isomer specificity (25)(26)(27).…”

Section: Conjrmatory Techiziques Usiizg Gclinsmentioning

confidence: 99%

Recent advances in ultratrace analysis of dioxins and related halogenated hydrocarbons

Afghan¹,

Carron²,

Goulden³

et al. 1987

Can. J. Chem.

View full text Add to dashboard Cite

Can. J. Chem. 65, 1086Chem. 65, (1987.Analytical methodology for polychlorinated dioxins and furans (PCDDs and PCDFs) in environmental samples is not standardized. Many variations exist for the extraction, cleanup, quantitation, and confirmation of these compounds and reported detection limits and recoveries vary over several orders of magnitude. This paper describes research carried out at the Canada Centre for Inland Waters over the past seven or eight years to develop reliable methodology at ultratrace levels (10-'2-10-l 5 g/g) applicable to a wide range of environmental samples. Extraction techniques are described for biological tissue (fish, clams, leaches, eggs), fly ash, sediments, and water. Detailed cleanup procedures for the various matrices consist of most or all of the following: gel permeation chromatography liquid/liquid extraction with Na3P04, liquid/liquid extraction with H2S04, basic alumina chromatography, and carbon fibre chromatography. Preliminary screening of the cleaned extracts is achieved by gas chromatography equipped with a mass selective detector and positive identification by gas chromatography /mass spectrometry operated in electron impact and chemical ionization modes and with full scan and multiple ion detection. Custom software permitting the analysis of a wide range of compounds in a single run by gc/ms is reported. The presence of specific isomers of PCDDs and PCDFs is confirmed by high resolution gas chromatography /mass spectrometry. A radioimmunoassay screening procedure for PCDDs in environmental samples is also described. Les mtthodes d'analyse des dioxinnes et des furannes polychlorts (DPC et FPC) ne sont pas standardisees. Plusieurs variations existent pour l'extraction, le nettoyage, la quantification et la confirmation de la prtsence de ces composCs; de plus, les limites de dttection ainsi que les taux de rtcuptration rapportCs varient par plusieurs ordres de grandeur. Dans ce travail, on dtcrit les etudes effectukes au cours des 7 a 8 dernikres anntes au centre canadien des eaux inttrieures dans le but de dtvelopper une mtthodologie applicable a des niveaux d'ultratraces (lo-" h 10-g/g) et a un grand Cventail d'tchantillons prtlevts dans I'environnement. On dtcrit des techniques d'extraction pour des tissus biologiques (poissons, moules, eaux de lessivage et oeufs), des suies, des sediments et des tchantillons d'eau. Les diverses mCthodes dCtaillCes proposCes pour le nettoyage de diverses matrices comportent la plupart ou toutes les techniques suivantes: chromatographie par permCation de gel; extraction liquide/liquide avec du Na3P04; extraction liquide/liquide avec du &So4; chromatographie standards sur de l'alumine ou des fibres de charbon.On a effectut des essais prtliminaires sur des extraits IavCs en faisant appel a la chromatographie en phase gazeuse couplte h un dttecteur sClectif de masses; on a proctdC I'identification positive par chromatographie en phase gazeuse couplCe la spectromCtrie de masse, optrCe soit dans le mode d'impact Clectronique ou d'ionisat...

show abstract

Capillary gas chromatography/atmospheric pressure negative chemical ionization mass spectrometry of the 22 isomeric tetrachlorodibenzo-p-dioxins

Cited by 60 publications

References 54 publications

Ionization mechanisms related to negative Ion APPI, APCI, and DART

Ionization mechanisms related to negative Ion APPI, APCI, and DART

Determination of polychlorinated dibenzo‐p‐dioxins, dibenzofurans, and biphenyls by gas chromatography/mass spectrometry in the negative chemical ionization mode with different reagent gases

Recent advances in ultratrace analysis of dioxins and related halogenated hydrocarbons

Contact Info

Product

Resources

About