Fingermark detection on non-porous and semi-porous surfaces using NaYF4:Er,Yb up-converter particles

Visualisation of latent fingermarks on polymer banknotes using copper vacuum metal deposition: A preliminary study

“…The use of upconversion powders, such as that by Ma et al, has been suggested as an alternative method to help overcome problematic backgrounds [9]. Tahtouh et al also utilised IR imaging in the form of Fourier transform infrared (FTIR) to enhance fingermarks on a number of substrates, including polymer banknotes, which contained untreated and cyanoacrylate treated fingermarks [10].…”

Improving pure red upconversion emission of Co-doped Y2O3:Yb3+–Er3+ nanocrystals with a combination of sodium sulfide and surfactant Pluronic-F127

“…However, the most efficient upconverting phosphors are yttrium-based inorganic crystals, such as yttrium oxide (Y 2 O 3 ) [11,33], yttrium fluoride (YF 3 ) [34], yttrium oxysulfide (Y 2 O 2 S) [34][35][36], and sodium yttrium fluoride (NaYF 4 ) [37,38]. Interestingly, yttrium oxide was one of the first inorganic crystals to be studied in detail in the nanophase as many synthetic procedures were developed, most of which involve relatively straightforward and simple processes.…”

Selective targeting of fingermarks using immunogenic techniques

“…Nanoparticles, naturally derived products, and the use of near-infrared and antiStokes luminescence are all novel areas that are currently being researched, with many providing promising results. It is not in the scope of this article to review these other novel techniques but a number of articles have already been published in these fields and the interested reader is directed there 2,6,9,11,[15][16][17][18][19][20][21][22] .…”