*
Diphenylamine
from ink
Diphenylamine
fromNIST library
Ink/paper
Paper only
Figure8
.
Overlaid TICs of paper, and paper with ink scribbles, as analyzed using SPME
GC-TOFMS. Diphenylamine (blue asterisk, inset chromatogram), whichwas located automatically
with a Compare feature of ChromaTOF, can be attributed to the ballpoint pen ink.
Conclusions
SPME GC-TOFMS is a fast and powerful way to characterize the volatile organic composition of ink
samples, especially due to automated peak find and spectral deconvolution. Compare, a feature
unique to ChromaTOF software, simplifies data reduction for complex samples, and quickly
highlights (and identifies) compounds that can be considered as "Contaminants" when compared to
a Reference. SPME needs further investigation as an ink dating technique for samplesmore than
eight months old.
References
G.M. LaPorte, J.D. Wilson, A.A. Cantu, S.A. Mancke, and S.L. Fortunato, The Identification of
2-Phenoxyethanol in Ballpoint Inks Using Gas Chromatography/Mass Spectrometry—Relevance to
Ink Dating
, J. Forensic Sci.
, Jan. 2004, Vol. 49, No. 1
V.N. Aginsky, Current Methods for Dating Ink on Documents
Acknowledgment
Gerald LaPorte at the United States Secret Service inWashington, DC provided the aged ink
samples. Chris Cox at Restek Corporation provided the Rtx-TNT column used for this work.
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