Spectroscopic Detection of Exogenous Material in Fingerprints After Development with Powders and Recovery with Adhesive Lifters

• NCJ Number: 221724
• Journal: Forensic Science International Volume: 174 Issue: 1 Dated: January 2008 Pages: 1-5
• Author(s): Matthew J. West; Michael J. Went
• Date Published: January 2008
• Length: 5 pages
• Publication Format: Article
• Publication Type: Report (Study/Research)
• Language: English
• Country: United States of America

Annotation

This study investigated the technique of Raman spectroscopy for the detection of drugs and other exogenous substances present in latent fingerprints

Abstract

Results indicated that the application of powders to develop contaminated latent fingerprints did not prevent the identification of the contaminant from the Raman spectrum obtained. The application of powder also had the advantage of reducing spectral interference from background fluorescence attributed to the sebaceous content of latent fingerprints. The application of the powder did result in an increase in the time taken to locate particles of the contaminant due to the physical presence of more material within the fingerprint. Typically there was a four to five fold increase in the analysis time. However, once located, the Raman spectra obtained allowed the successful identification of the contaminant. Contaminated fingerprints developed with powder and then lifted with tapes showed again that successful detection was still possible. There were some complications encountered with problems attributed to fluorescence from backing sheets that lifted prints were attached to, and with interference from strong Raman bands associated with the hinge lifters used. These problems can be overcome by the use of backing sheets with no fluorescence, or the use of lifters with no strong Raman bands to interfere with detection. Spectral subtraction of Raman bands associated with tapes used in the lifting process is another method that could be employed to remove interfering bands. Raman spectra obtained from powered and lifted fingerprints within evidence bags were also obtained, and again, successful identification of the contaminant was made. This is of particular importance as it means that items do not have to be removed from evidence bags to be examined, thereby reducing potential for contamination, and also the chain of evidence remains preserved. Figures, references