Curcumin Analogues as Organic Fluorophores for Latent Fingerprint Imaging

Synthesis and characterization of two curcumin analogues BAA and Br-AA via a condensation reaction was reported. Both the synthesized organic luminophores exhibited aggregation-induced emission (AIE) with bright yellow and green emission respectively. Increase in the water% enhanced the emission by both the compounds confirmed the AIE property. A detailed study of latent fingerprints visualization was also carried out for both the analogues. Both the compounds showed good to normal capability to develop latent fingerprints (LFPs). Compound BAA performed better as a fluorescent material to develop LFPs compared to Br-AA. The LFPs developed were analyzed to obtain 1-3 level of fingerprint patterns under UV 365 nm illumination. The LFPs developed using BAA exhibited excellent efficiency, sensitivity, high contrast with low background interreference. All three levels of fingerprint patterns were identified by BAA. However, Br-AA showed inability to develop high clarity images of latent fingerprints. The solid-state emission nature of the analogues was also evaluated from their emission spectra and CIE coordinates were found to be were (0,187, 0.518) and (0.265, 0.484) for BAA and Br-AA respectively.