TITLE:
Mass Spectrometric Imaging of Gold Nanolayer Coated Latent Fingermarks: Deciphering Overlapping Features by Statistical Analysis
AUTHORS:
Christian Elsner, Bernd Abel
KEYWORDS:
Overlapping Latent Fingermarks, Mass Spectrometry Imaging, Statistical Analysis
JOURNAL NAME:
Advances in Chemical Engineering and Science,
Vol.6 No.5,
December
20,
2016
ABSTRACT: Overlapping
latent fingermarks constitute a serious challenge to database related
recognition and matching algorithms in biometry, forensic and crime scene
investigations. Mass spectrometry imaging (MSI) is a powerful tool for
deciphering and analyzing overlapping fingermarks based on the individual
chemical information of each deposit. Fingermark MSI in practice still requires
a subjective judgment of an MSI expert, such that rapid analysis, automation,
standardization, and a quantitative evaluation of the complete detection and
separation process of overlapped fingermarks from MSI data sets is the ultimate
goal and will be necessary to become an accepted process in criminal
investigations and law enforcement. Here we investigated the feasibility and
efficiency of different statistical approaches for the separation of overlapped
latent fingermarks based on MSI data. Entropy analysis of generated m/z-images was used to evaluate the
results obtained from the statistical analysis. Furthermore, we demonstrate and
discuss the opportunity to reconstitute and separate overlapping fingermarks by
discrete scanning at selected x,y-positions defined from a previous image
analysis using a more simple schema based on visible and therefore optical
distinguishable overlapped ink-based fingermarks. The overlapped latent
fingermarks were developed by rapid gold sputter coating and analyzed by laser
based MSI, without (organic) matrix preparation. Latent finger marks can be
transferred from the substrate/surface with and conserved on a soft gold
sputtered soft membrane at low temperatures.