Total alkylated polycyclic aromatic hydrocarbon characterization and quantitative comparison of selected ion monitoring versus full scan gas chromatography/mass spectrometry based on spectral deconvolution.
Quantitative information of alkylated PAH is frequently used in forensic investigations to characterize petroleum releases and fate in the environment. Interference from a complex matrix often obviates target compound quantitation. Using single ion SIM or a single mass spectral pattern to analyze these homologs should result in either over- or underestimating their concentration. To confirm this hypothesis, a library of C(1)-C(4) alkylated PAH fragmentation patterns were made from automated sequential two-dimensional GC-GC/MS data and the Ion Signature deconvolution software. Based on these patterns, 1D GC/MS data was compared using single ion extraction and one fragmentation pattern per homolog against data obtained from those peaks whose scans met the spectral deconvolution criteria. Significant overestimation occurs when a single ion is used to extract peak signal for C(4)-naphthalene, C(1)-fluorene, and the C(1)- to C(3)-dibenzothiophenes. In contrast, C(2)-naphthalene, C(2)-fluorene, C(3)-phenanthrene, and C(1)-dibenzothiophene were underestimated by >50% when one fragmentation pattern per homolog was used. The Ion Signature deconvolution software makes it easy to interpret mass spectrometry data, especially in complex environmental samples like diesel fuel.
Zeigler
Christian
C
Tufts University, Chemistry Department, 62 Talbot Avenue, Medford, MA 02144, USA.
Macnamara
Kevin
K
Wang
Zhendi
Z
Robbat
Albert
A
D004784:Environmental Monitoring / Q000379:methods; D044707:Forensic Sciences / Q000379:methods; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D005742:Gasoline / Q000032:analysis; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*
D005742:Gasoline; D011084:Polycyclic Aromatic Hydrocarbons