Substituted naphthoquinones as novel amino acid sensitive reagents for the detection of latent fingermarks on paper surfaces

Abstract

In this paper, we present our preliminary studies into naphthoquinones as novel reagents for the detection of latent fingermarks on paper. Latent fingermarks deposited on paper substrates were treated with solutions of selected naphthoquinones in ethyl acetate/HFE-7100, with subsequent heating. The selected compounds were 1,4-dihydroxy-2-naphthoic acid, 1,2-naphthoquinone-4-sulfonate, 2-methoxy-1,4-naphthoquinone and 2-methyl-1,4-naphthoquinone. All of the tested compounds yielded purple-brown visible fingermarks, which also exhibited photoluminescence when illuminated with a high intensity filtered light source at 555 nm and viewed through red goggles. Indirect heat using an oven at 150 °C for 1 hour was found to be superior to direct heat with an iron, which while providing faster development lead to increased levels of background colouration. Luminescence spectrophotometry revealed differences in photoluminescence characteristics for fingermarks developed with the different naphthoquinones, with excitation over the range 530-590 nm. Luminescence spectrophotometry of developed lysine, glycine and serine spots on paper was used to confirm that the naphthoquinones were reacting with amino acids in the latent fingermark.

A portable optical human sweat sensor

“…HNQ was used as a biological marker to detect latent fingermarks on paper surfaces. 10 Aqueous HNQ solutions were also used to detect pH changes. 11 A cyanide and acetate sensor was implemented using HNQ optical properties.…”

Performance of 1,2-indanedione and the need for sequential treatment of fingerprints

“…There have been numerous communications discussing reagents or formulations of reagents with a higher yield in visualised fingermarks [8][9][10][11][12][13][14].…”

The effect of Na+ and K+ doping on the properties of sol-gel deposited 2-hydroxy-1,4-naphthoquinone thin films

“…18,19 HNQ and its derivatives were also used to detect latent finger prints on paper surfaces for criminal investigation. 20 Very recently, a sensitive cyanide and acetate sensor has been proposed, which would utilize a HNQ medium. 21 The spectral and theoretical properties of HNQ as a bulk material have been investigated and are well understood.…”