Surface Modification for the Collection and Identification of Fingerprints and Colorimetric Detection of Urea Nitrate

Abstract

Glass surfaces were modified with a combination of dyes and reagents to allow for the potential simultaneous recording of a detailed fingerprint and the detection of the explosive urea nitrate (UN), as a proof of principle of surface modification for simultaneous linking of identity to manipulation of explosives. By coating microscope slides with 9,10-diphenylanthracene (DPA), p-dimethylaminobenzaldehyde (p-DMAB) and p-dimethylaminocinnamaldehyde (p-DMAC), a colorimetric change was observed in the presence of UN, while revealing a fingerprint with enough resolution to isolate at least 10 minutiae. This is the first step in creating point-of-care devices capable of detecting low concentrations of explosives and drug metabolites and connecting them to a fingerprint.

A Rapid and Specific Method for the Detection of Indole in Complex Biological Samples

“…From the same bacterial culture, the Kovács assay detected 4.7 Ϯ 0.33 mM, compared to 3.3 Ϯ 0.22 mM using the HIA. The discrepancy in the amounts of indole detected between the two methods is consistent with the known observation that the Kovács assay, although very sensitive, will also detect 3-methylindole (skatole), a common indole analog in biological materials, including bacterial cultures (18)(19)(20)(21)(22)(23)(24)(25). These results suggest that 3-methylindole may be present in the culture medium and is probably responsible for increasing the estimation of indole by a significant percentage (30% in this experiment).…”

“…Currently, the Kovács assay (13)(14)(15)(16)(17) is the most widely used method for detecting indole-producing bacteria. However, the key component, para-dimethylaminobenzaldehyde, reacts with a wide variety of indolecontaining compounds (18)(19)(20)(21)(22)(23)(24)(25). As a result of this nonspecificity, the Kovács assay cannot be used to reliably quantitate indole in complex biological samples.…”

A March to Shape Optical Artificial Olfactory System toward Ultrasensitive Detection of Improvised Explosives

“…[ 112 ] Shoronia et al used 4‐dimethyl‐aminocinnamaldehyde to react with nitrourea in neutral environment to form a red protonated Schiff base structure, which is the condensation reaction product between amino group and carbonyl group, and thus realized the detection of residue on fingers (Figure 4b). [ 113 ] The reaction mechanism was characterized in detail, and it was proved that the reaction process was the condensation reaction of amino group and carbonyl group, and the red protonated Schiff base structure dye was finally produced.…”

“…Reproduced with permission. [ 113 ] Copyright 2015, Wiley‐VCH. c) Detection of H 2 O 2 by nanomagnet‐silica shell(Fe 3 O 4 @SiO 2 ) decorated with Au@Pd nanoparticles.…”

“…[112] Shoronia et al used 4-dimethyl-aminocinnamaldehyde to react with nitrourea in neutral environment to form a red protonated Schiff base structure, which is the condensation reaction product between amino group and carbonyl group, and thus realized the detection of residue on fingers (Figure 4b). [113] The reaction Researches on optical detection of hypochlorite, [41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56][57] perchlorate, [58][59][60] peroxide, [61][62][63][64][65][66][67][68][69][70][71][72][73][74][75][76][77] nitrate, [78][79][80][81][82][83][84][85] and nitrite…”