Nanoscale Analysis of the Interaction Between Cyanoacrylate and Vacuum Metal Deposition in the Development of Latent Fingermarks on Low‐Density Polyethylene*

Abstract

Vacuum metal deposition (VMD) has been previously demonstrated as an effective development technique for latent fingerprints, and in some cases has been shown to enhance prints developed with cyanoacrylate (superglue) fuming. This work utilises scanning electron microscopy (SEM) to investigate the interactions of the two development techniques when applied to latent fingerprints on low density polyethylene (LDPE). Cyanoacrylate (CA) is shown to act principally on the eccrine deposits around sweat pores, where polymerisation results in long polymer fibrils a few hundred nanometres in width. Subsequent VMD processing results in additional areas of development, for example between pores. However, the primary mode of deposition of zinc is by interaction with the polymerised CA, the fibrils of which become decorated with zinc nanoparticles. Areas with limited CA deposition and no significant polymerisation are also enhanced with the VMD process, resulting in increased print development.

Optimized Development of Sebaceous Fingermarks on Nonporous Substrates with Conformal Columnar Thin Films

“…) developed very well using cyanoacrylate fuming followed by the deposition of a 50‐nm‐thick CTF of gold. Quite likely, the success was facilitated by the formation of nanofibers of cyanoacrylate that provided nucleation sites at different elevations on the fingermark for the CTF to grow on. The hybrid cyanoacrylate‐CTF technique appears promising and requires further research.…”

Exposing latent fingermarks on problematic metal surfaces using time of flight secondary ion mass spectroscopy

“…These include, but are not limited to, ninhydrin [7], powder development [8], vacuum metal deposition (VMD) [9], physical developers [10], small particle reagents [11], and cyanoacrylate (CNA, superglue) fuming [12]. The choice of technique or reagent being used in each case has been optimised to account for the composition of the fingermarks and the physical and chemical properties of the surface/substrate on which the fingermark is believed to have been deposited [4].…”

Migration of latent fingermarks on non-porous surfaces: Observation technique and nanoscale variations

“…Several factors such as surface texture, physicochemical properties, curvature, temperature, electrostatic forces and surface free energy have been also suggested to affect the latent fingermarks [5,22,27,28]. Surfaces which appear smooth to the eye often have micro or sub-micro scale roughness including topographical linear features such as ridges, valleys and scratches which affect the behaviour of the latent fingermark on the surface, as well as the development agent interaction [27,29,30].…”