ION-MOLECULE REACTIONS OF HALOCARBON CATIONS WITH POLYCYCLIC AROMATIC-HYDROCARBONS IN A QUADRUPOLE ION-TRAP - PART II - APPLICATIONS TO ENVIRONMENTAL-ANALYSIS
Aa. Mosi et al., ION-MOLECULE REACTIONS OF HALOCARBON CATIONS WITH POLYCYCLIC AROMATIC-HYDROCARBONS IN A QUADRUPOLE ION-TRAP - PART II - APPLICATIONS TO ENVIRONMENTAL-ANALYSIS, Journal of mass spectrometry., 33(3), 1998, pp. 250-263
Ion-molecule reactions between the cations CH3CHF+ and CH3CF2+ generat
ed from 1,1-difluoroethane and gas chromatographic eluents from a sedi
ment extract containing polycyclic aromatic hydrocarbons (PAHs) were u
sed to differentiate goups of PAH structural isomers, Formation of spe
cific adducts led to characteristic mass spectra for the different iso
mers. Differences in the ion chromatograms for M+, MH+, [M+CH3CHF](+),
[M +CH3CHF-HF](+), [M+CH(3)CF2](+) and [M+CH3CF2-HF](+) (M=PAH molecu
le) allowed the resolution of co-eluting isomers. As the ratio of yiel
ds of adducts was not changed by methyl substitution, it was possible
to differentiate and quantitate alkylated PAHs for which standards wer
e not available, By performing a series of transformations between the
ion chromatograms of the most characteristic;adducts, information on
individual isomer groups could he deconvoluted from complex clusters o
f isomers. This ion trap/chemical ionization technique displayed calib
ration curse parameters similar to those for electron ionization analy
sis and limits of detection of 170 pg in the sediment extract. (C) 199
8 John Wiley & Sons, Ltd.