Benzoic acid derivatives as luminescent sublimation dyes in cyanoacrylate fuming of latent fingerprints

Development of latent prints employing cyanoacrylate ester (CA) can be a multistep process including CA fuming and subsequent fluorescent staining to produce fingerprints of sufficient contrast for comparison work. To enable a single-step CA fuming-staining process, a selection of fluorophores have been developed as sublimation dyes in CA fuming. A greater array of such luminescent sublimation dyes would allow users greater flexibility in selecting a particular dye-CA combination to best suit their processing needs. Toward this end, six benzoic acid derivatives were evaluated for use as luminescent sublimation dyes under elementary CA fuming conditions using a single non-porous surface type and an inexpensive handheld UV lamp for excitation. Two benzoic acid derivatives, 2-hydroxybenzoic acid (salicylic acid) and 2-aminobenzoic acid (anthranilic acid), were identified as new potential luminescent sublimation dyes with stained fingerprints excited at 254 nm. The fluorescence intensity and stability of prints produced via the sublimation of CA with 2-hydroxybenzoic acid and 2-aminobenzoic acid were evaluated over approximately six weeks using image and statistical analysis.

Automated summary

This study evaluated six benzoic acid derivatives as potential luminescent sublimation dyes, identifying 2-hydroxybenzoic acid and 2-aminobenzoic acid as promising new dyes for staining fingerprints excited at 254 nm. The fluorescence intensity and stability of prints produced with these two derivatives were evaluated over approximately six weeks, providing new options for future CA fuming processes.