ISSN: 0022-1198
CODEN: JFSCA
Page Count: 10

Evaluation of Desorption/Ionization Mass Spectrometric Methods in the Forensic Applications of the Analysis of Inks on Paper
Grim, DM
Michigan State University, MI

Allison, J
Michigan State University, MI

Siegel, J
School of Criminal Justice, Michigan State University, MI

(Received 5 September 2000; accepted 29 January 2001)

Abstract

Fast atom bombardment and laser desorption mass spectrometry (LDMS) provide molecular level information concerning an ink's composition. Two ink-jet printer inks, Ink A containing the cationic dye Methyl Violet 2B, and Ink B containing the anionic dye, Solvent Black, were studied. Both positive and negative ion detection modes of the mass spectrometer were used. LD may be used for the analysis of inks on paper. Once on paper, the ink's solvent system has evaporated, leaving mainly the dyes behind, which are detected using LDMS. An ink fades with time, indicating that the dyes are degrading. Preliminary results from an accelerated aging study of ballpoint pen ink using UV irradiation confirm that dye degradation products are formed. The degradation chemistry follows an oxidative demethylation process for which all products formed are detected using LDMS. Results suggest that LDMS may be developed to determine the relative age of inks.

Keywords:
forensic science, questioned documents, ballpoint pen ink, accelerated aging, mass spectrometry

Paper ID: JFS15164J
DOI: 10.1520/JFS15164J
ASTM International is a member of CrossRef.