title: Evaluation of four mass spectrometric methods for the gas chromatographic analysis of polychlorinated n-alkanes.
abstract: The suitability of four mass spectrometric methods for the gas chromatographic analysis of polychlorinated n-alkanes (PCAs, also called chlorinated paraffins) was evaluated and compared using spiked and fish liver samples. Electron ionization tandem mass spectrometry (EI-MS/MS) as well as electron capture negative ionization (ECNI) combined with low and high resolution mass spectrometry and CH4/CH2Cl2-negative ion chemical ionization (NICI) low resolution mass spectrometry were investigated. All methods showed an accuracy of <21% for the analysis of spiked fish samples. However, the analysis of real samples showed deviations of up to 46% between the four mass spectrometric methods. The influence of the selected reference standard on quantification was also evaluated. The use of a quantification standard with a degree of chlorination deviating from that of the sample can result in differences of > 100% for the ECNI methods. EI-MS/MS and CH4/CH2Cl2-NICI led to errors of maximum 17% and 33%, respectively, independent from the degree of chlorination of the used reference standard.
authors.affiliation: Organic Analytical Chemistry, University of Basel, Neuhausstr. 31, 4057 Basel, Switzerland.
authors.forename: Zdenek
authors.initials: Z
authors.lastname: Zencak
authors.forename: Anders
authors.initials: A
authors.lastname: Borgen
authors.forename: Margot
authors.initials: M
authors.lastname: Reth
authors.forename: Michael
authors.initials: M
authors.lastname: Oehme
mesh_terms: D000473:Alkanes / Q000032:analysis*; D000818:Animals; D002849:Chromatography, Gas / Q000379:methods*; D005399:Fishes; D006843:Hydrocarbons, Chlorinated / Q000032:analysis*; D008099:Liver / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods*; D012015:Reference Standards
chemical_list: D000473:Alkanes; D006843:Hydrocarbons, Chlorinated