Relevant visualization technologies for latent fingerprints on wet objects and its challenges: a review

Abstract

Fingerprint has been one of the powerful evidence in forensic investigation as it is useful for human identification, associating an individual to an item and/or location of interest, as well as reconstructing the crime scenes. Considering that latent fingerprints are commonly found at crime scenes and that it requires the use of fingerprint visualization methods due to its hidden nature, continuous research in developing suitable methods has been reported. However, the underlying physical and/or chemical interactions for certain visualization methods that have successfully visualized wet fingerprints remains unreported. This is probably because previous studies were primarily focused on establishing the fingerprint contrast rather than the comprehension of the physical and chemical aspects behind it. A good understanding on such aspects may prove useful in guiding future improvements, or modifications of existing fingerprint visualization methods. Hence, this review paper focuses on wet latent fingerprints, difficulties in the available wet fingerprint visualization methods, as well as its overview of the challenges and future insights.

Eu-Doped Pyrochlore Crystal Nano-Powders as Fluorescent Solid for Fingerprint Visualization and for Anti-Counterfeiting Applications

“…Level 2 details give information about pattern agreement of the ridges of individual fingerprints. Level 3 details are defined as fingerprint ridge dimensional features, including sweat pores, curvature, and dots [ 33 ].…”

Interpol review of fingermarks and other body impressions 2016–2019

“…Overall, the results were in accordance with previously-published studies related to VMD applied to polymers and other non-porous substrates. Available reviews : detection of fingermarks on wetted items [ 491 ]. Acronyms used : CA (cyanoacrylate), PE (polyethylene), PVC (polyvinylchloride), RAM (mix of Rhodamine 6G, Ardrox, and 7-[p-methoxybenzylamino]4-nitrobenzene-2-oxa-1,3-diazole), SPR (small particle reagent), VMD (vacuum metal deposition), VMD Ag (silver-based monometallic VMD), VMD Au/Zn (traditional gold-zinc VMD), VMD St-Ag (sterling silver-based monometallic VMD) …”

Preliminary forensic assessment of the visualised fingerprints on nonporous substrates immersed in water using the green and optimised novel nanobio-based reagent

“…This observation was also consistently seen in our previously reported studies 34 , 35 . As for the SPR, the mode of interaction for the visualisation of fingerprints on wet, non-porous substrates remains unknown 23 ; thus, suitable discussion on its preference on the non-water soluble constituents of fingerprints proves limited.…”

“…Being commercially available globally, SPR is commonly used for on-site visualisations by presumably capitalising on the lipids of fingerprints 1 , 22 . Despite the common usage of SPR, its mode of interactions underlying successful visualisation remains in dispute 23 . Typically, the commercially-available SPR (manufactured by Sirchie) is mainly made up of fine particles of either titanium dioxide (TiO 2 ) (white), molybdenum (IV) sulphide (MoS 2 ) (black) or invisible green (Sirchie proprietary fluorescent product) suspended in surfactant, and some, with the combination of ether and water 24 – 26 .…”