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  • 1
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Microcolumn Separations 6 (1994), S. 605-616 
    ISSN: 1040-7685
    Keywords: GC-AED ; optimization of response ; PCBs ; methylsulfonyl-PCBs ; biological samples ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Gas chromatography-atomic emission detection (GC-AED) has been evaluated in order to determine the optimal conditions for chlorine and sulfur response of chlorinated biphenyls (CBs) and methylsulfonyl metabolites of CBs (MeSO2-CBs). The influence of the shape of the capillary column end facing the plasma, make-up gas flow, additional transfer line make-up gas flow and reagent gas flows on the detector response has been studied. Using an additional make-up gas flow applied through a transfer line capillary having a decreased outlet diameter yielded an increased detector response with minimum detectable levels for sulfur and chlorine of 1.7 and 20 pg, respectively. Further, a substantial decrease in peak tailing was achieved. The applicability of the method for analysis of biological materials is demonstrated by the determination of the main CB congeners present in human blood and of MeSO2-CBs in seal blubber.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 15 (1992), S. 745-750 
    ISSN: 0935-6304
    Keywords: On-line coupling ; LC-GC ; LC-GC-MS ; Liquid chromatography ; Gas chromatography ; Mass spectrometry ; Chlorinated polycyclic aromatic hydrocarbons ; Urban air ; Occupational exposure measurement ; Bus drivers ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Coupled liquid chromatography - gas chromatography - mass spectrometry (LC-GC-MS) has been applied for on-line clean up, separation, and identification of chlorinated polycyclic aromatic hydrocarbons (CI-PAHs). A loop-type interface was used to couple the liquid chromatograph on-line with the GC-MS, and concurrent solvent evaporation was used for sample transfer.A back-flush technique was used in conjunction with a two-dimensional column system for isolation of CI-PAHs and polycyclic aromatic hydrocarbons (PAHs). This fraction was transferred on-line to the GC and separated on a capillary column. Selective and sensitive detection of CI-PAHs in the GC eluate was obtained by negative ion chemical ionization (NICI) mass spectrometry and selected ion monitoring (SIM).The combined on-line system for isolation, separation, and identification showed high precision and accuracy, and demonstrated a linear response from 1 to 1000 pg for chlorinated PAHs. The estimated detection limit was 250 fg for 1-chloropyrene and 1,6-dichloropyrene.The technique was demonstrated by analysis of urban air samples. The low detection limit made it possible to use the technique for analysis of personally carried monitoring equipment for measurement of exposure to CI-PAHs in the work environment.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 18 (1995), S. 685-691 
    ISSN: 0935-6304
    Keywords: On-line LC-GC-MS ; PCBs ; Non-ortho CBs ; Human blood plasma ; Dinitroanilinopropyl modified silica ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A method for the determination of non-, mono- and di-ortho substituted polychlorinated biphenyls in human blood plasma is presented. The non-ortho CBs are isolated from the bulk of PCBs by HPLC on a dinitroanilino-propyl silica column and collected as a heart-cut fraction that is transferred on-line to GC-MS utilizing concurrent solvent evaporation technique. The on-line coupling serves to lower the limit of determination and to partly automate the sample clean-up. The di- and mono-ortho CBs are analyzed by off-line GC-ECD using two different columns. Sample pre-treatment is performed by extraction with organic solvents and fractionation on silica gel. A high reproducibility and an absolute over-all recovery of approximately 70 % is demonstrated. The method is applied to samples of blood from 5 individuals. All the samples demonstrated a similar relative concentration profile. It was also shown that three CB congeners (CB 126, CB 156 and CB 170) contributed to the major part of the toxic equivalent quantity of the PCB content in the blood.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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