NCJ Number
212916
Journal
Journal of Forensic Sciences Volume: 51 Issue: 1 Dated: January 2006 Pages: 57-63
Date Published
January 2006
Length
7 pages
Annotation
Using micro-X-ray fluorescence (MXRF), this experiment tested whether both visible and latent fingerprints could be detected based on their elemental composition.
Abstract
The testing showed the feasibility of analyzing fingerprints by MXRF, although limitations were found. Knowledge of the general location of a fingerprint is required in order to examine the sample with the MXRF instrument. If a faint or partial print could be located by conventional powder or chemical development, MXRF could be used to scan the location in order to generate a complete print, assuming that the conventional visualization treatments did not completely remove the element detectable by the MXRF. MXRF was found to increase the detectability of fingerprints that carry elements of gunpowder, lotion, sunscreen, saliva, or certain food residue, based on inorganic elemental constituents. MXRF is currently capable of imaging a variety of elements across surfaces up to several hundred cm squared in size, with a spatial resolution that ranges from a few micrometers to a few 100 mm. Thus, the MXRF imaging resolution and macroscopic capabilities are ideal for detecting fingerprints. X-ray fluorescence (XRF) involves irradiating a sample with a primary X-ray beam and detecting X-rays emitted from the sample. The energies of these emitted X-rays are characteristic of the elements present in the sample. This report's description of materials and methods addresses instrumentation; sample preparation; and the testing of sebaceous fingerprints and fingerprints carrying perspiration, lotion, saliva, banana, and sunscreen on black substrate. 8 figures and 25 references