A novel approach to fingerprint visualization on paper using nanotechnology: reversing the appearance by tailoring the gold nanoparticles' capping ligands

Abstract

Gold nanoparticles, AuNPs, capped with mercaptocarboxylic acids followed by silver precipitation develop latent fingermarks on paper as high quality "negative" impressions. This effect stems from hydrogen bonding between the carboxylic group and the paper cellulose and may improve the yield of latent fingermarks since the results are less dependent on sweat composition.

Further investigations into the single metal deposition (SMD II) technique for the detection of latent fingermarks

“…Finally, samples categorised as 'reversed development' appeared to experience heavy pink background staining of the substrate yet no staining of the fingermark ridges, generally resulting in the so-called reverse fingermark, or in some cases a blank space where the fingermark was situated. A similar phenomenon has been noted on paper surfaces when using gold nanoparticles modified to specifically target the cellulose substrate (38,39). In this work we did not observe reversed or "empty" developed marks on paper, which is not surprising as the gold nanoparticles were not modified as those in the earlier work by Almog and co-workers.…”

Fingerprint composition and aging: A literature review

“…Recent advances have focussed on the development of novel enhancement methods and the optimisation of existing reagents [4][5][6][7][8][9][10][11]. Secondly, research has explored intelligence gathering through individualisation from the intrinsic composition.…”

Enhancing the visualization of latent fingerprints by aggregation induced emission of siloles

“…For example, chemical imaging techniques utilizing Raman, 4,5 FTIR, [6][7][8] and mass spectrometry, [9][10][11] have signicantly improved the study of ngerprint composition because of their ability to identify and map the compounds present in ngerprint residues. Additionally, the application of nanoparticles (NPs), including gold NPs, [11][12][13][14][15] TiO 2 particles, 16 nano-structured ZnO, 17 and quantum dots, 18,19 for ngerprint detection has also attracted considerable interest. 3 LFPs can also be detected by uorescence approaches which exhibit a much higher sensitivity than those based on color formation.…”