title: Spectroscopic detection of exogenous materials in latent fingerprints treated with powders and lifted off with adhesive tapes.
abstract: Fingerprint evidence offers great value to criminal investigations since it is an internationally recognized and established means of human identification. With recent advances in modern technology, scientists have started analyzing not only the ridge patterns of fingerprints but also substances which can be found within them. The aim of this work was to determine whether Fourier transform infrared (FTIR) spectromicroscopy could be used to detect contamination in a fingerprint which was dusted with powder (a technique already recognized as an effective and reliable method for developing latent fingerprints) and subsequently lifted off with adhesive tape. Explosive materials (pentaerythritol tetranitrate, C-4, TNT) and noncontrolled substances (sugar, aspirin) were used to prepare contaminated fingerprints on various substrates. Freshly deposited fingermarks with powders which were lifted off with adhesive tapes (provided by Singapore Police Force) were analyzed using a Bruker Hyperion 2000 microscope at the ISMI beamline (Singapore Synchrotron Light Source) with an attenuated total reflection objective. FTIR spectroscopy is a nondestructive technique which requires almost no sample preparation. Further, the fingerprint under analysis remains in pristine condition, allowing subsequent analysis if necessary. All analyzed substances were successfully distinguished using their FTIR spectra in powdered and lifted fingerprints. This method has the potential to significantly impact forensic science by greatly enhancing the information that can be obtained from the study of fingerprints.
authors.affiliation: Singapore Synchrotron Light Source, National University of Singapore, 5 Research Link, 117603, Singapore, Singapore, slsba@nus.edu.sg.
authors.forename: A
authors.initials: A
authors.lastname: Banas
authors.forename: K
authors.initials: K
authors.lastname: Banas
authors.forename: M B H
authors.initials: MB
authors.lastname: Breese
authors.forename: J
authors.initials: J
authors.lastname: Loke
authors.forename: S K
authors.initials: SK
authors.lastname: Lim