Page 242 - Advances in Forensic Applications of Mass Spectrometry - Jehuda Yinon

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and potential publication of a GC/MS/MS method for fire debris analysis. A
single method approach with GC/MS/MS is actually an initial acquisition
segment, using a standard full-scan approach (GC/MS) to detect relatively
low molecular weight, and single-component, ignitable liquids, followed by
a series of MS/MS acquisition segments using the target class approach with
GC/MS/MS to address petroleum distillates and other mixtures.
The primary objective of GC/MS/MS analysis is to remove responses due
to pyrolysates that may complicate the interpretation of class ion chromato-
grams (e.g., ion at m/z 119 for dimethyl-benzenes/C2-benzenes). As seen in
Figure 5.19, the class profile for C2-benzenes is very comparable in the

GC/MS/MS REMOVES PYROLYSATES
file5270.ms
C2 - BENZENES
Sample by GC/MS
Coeluting interferents disrupt ion profile

f5271ms2.ms
MS/MS specificity removes interference
Sample by GC/MS/MS

s
Very good comparison to reference f3452ms2.ms
Gasoline Standard by GC/MS/MS

1 2 3 4 5

Figure 5.19 Interferents in GC/MS analysis (top ion profile) are removed by
GC/MS/MS providing excellent comparability to reference material (bottom ion
profile).

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