Detection and Identification of Explosive Particles in Fingerprints Using Attenuated Total Reflection‐Fourier Transform Infrared Spectromicroscopy

Abstract

The application of attenuated total reflection (ATR)-Fourier transform infrared (FTIR) spectromicroscopy for detection of explosive particles in fingerprints is described. The combined functions of ATR-FTIR spectromicroscopy are visual searching of particles in fingerprints and measuring the FTIR spectra of the particles. These functions make it possible to directly identify whether a suspect has handled explosives from the fingerprints alone. Particles in explosive contaminated fingerprints are either ingredients of the explosives, finger residues, or other foreign materials. These cannot normally be discriminated by their morphology alone. ATR-FTIR spectra can provide both particle morphology and composition. Fingerprints analyzed by ATR-FTIR can be used for further analysis and identification because of its non-destructive character. Fingerprints contaminated with three different types of explosives, or potential explosives, have been analyzed herein. An infrared spectral library was searched in order to identify the explosive residues. The acquired spectra are compared to those of finger residue alone, in order to differentiate such residue from explosive residue.

Detection of nitro-organic and peroxide explosives in latent fingermarks by DART- and SALDI-TOF-mass spectrometry

“…The characteristic spectral patterns associated with both DART and SALDI-systems can be used identify these explosives with good sensitivity and use of MS-MS via collision induced dissociation (CID) can add further un-ambiguous evidence for their identity. In contrast screens for explosives in fingermarks using IR/Raman spectroscopy [14,15] require further complex sample processing to obtain such MS identification. An example of the SALDI-MS-MS spectrum for PETN is shown in Fig.…”

Trends in fingerprint analysis

“…ATR-FTIR spectroscopy has also been used to detect other exogenous compounds such as components relating to explosives. In one particular study [34], trinitrotoluene (TNT), ammonium nitrate (AN), and trinitrobenzene (TNB) were successfully identified using ATR-FTIR spectroscopy. Another popular spectroscopic method is Raman spectroscopy.…”

Advances in the development and component recognition of latent fingerprints

“…Bhargava et al have reported the use of reflection-absorption mode for the distinction of overlapping fingerprints based on differences in their chemical origins [60]. FTIR imaging has been used to detect exogenous trace residues associated with forensic evidence, e.g., explosives [60][61][62] and illegal substances [63].…”