NCJ Number
186428
Journal
Journal of Forensic Sciences Volume: 45 Issue: 6 Dated: November 2000 Pages: 1286-1293
Date Published
November 2000
Length
8 pages
Annotation
This research used thin-layer chromatography (TLC) on sebum-rich fingermarks laid directly onto TLC plates; an argon ion laser was used to visualize the separated components.
Abstract
The research involved two separate experimental procedures. The first experiment developed a robust system for the separation of the fluorescent components in fingermark residue by TLC. The second experiment investigated the nature of the separated compounds through visualization treatments. Sample preparation did not use any washing or swabbing that could extract additional components from the skin surface. This provided a more realistic starting point for the analysis of fingermarks. The separated components fluoresce orange, green, and yellow/green (in order of decreasing Rf). This pattern of separation was reproducible for a range of male donors and for one donor over a period time. Elution of material may, however, be incomplete, since some fluorescence remains at the origin, and Band 1 sometimes appears to be two bands that have not been fully resolved. It is still not known whether the visibly excited fluorescence was due to some components secreted onto the skin surface or was due to materials of external origin, but in the future it should be possible to identify the separated compounds through an analytical method such as LC-MS with fluorescence detection. Alternatively, if the components are volatile, then it may be possible to use direct probe GC-MS and analyze the compounds directly off the TLC plates. The robustness of the TLC system as demonstrated by this study suggests numerous opportunities for studying and analyzing the fluorescence of fingermarks. 2 tables, 7 figures, and 27 references