NCJ Number
217244
Journal
Journal of Forensic Sciences Volume: 52 Issue: 1 Dated: January 2007 Pages: 209-215
Date Published
January 2007
Length
7 pages
Annotation
This paper describes further developments in a previously reported method for detecting 2-phenoxyethanol in ink.
Abstract
Using the method described, researchers were able to achieve the nondestructive analysis of volatile components of ballpoint pen inks on paper for the first time. The analysis requires minimum sample manipulation and can be repeated on different areas of a document. The results are consistent with a similar reported study in which the method successfully determined whether inks were less than 6 months old. It was possible to detect the presence of ink solvents on documents for a period of up to approximately 2 years. The next phase of the research will develop a method that can determine the approximate age of an ink based on inferences from one or a series of readings. The method used involved the solid-phase microextraction (SPME) sampling technique, together with gas chromatography-mass spectrometry (GC-MS). In order to avoid document destruction, which occurs in conventional methods of ink analysis, a sampling cell was constructed to allow solvents to be adsorbed directly onto the SPME fiber from the headspace above the document surface. Analytes (ink volatile components) are then desorbed from the SPME fiber on a gas chromatograph equipped with a mass selective detector. The description of the experiments addresses the selection of SPME fiber; chemicals, materials, and samples; instrumentation; sampling cell; general sample preparation and analysis; optimization of absorption time; optimization of sampling and equilibrium temperature conditions; calibration; the effect of paper surface on analytes adsorption on SPME fiber; sampling vial effects; and the application of the method to the new nondestructive sampling cell. 10 figures and 18 references