A butterfly-shaped ESIPT molecule with solid-state fluorescence for the detection of latent fingerprints and exogenous and endogenous ONOO- by caging of the phenol donor

The latent fingerprints (LFPs) at the crime scene are unique and stable, which are considered as an important clue in criminal justice and forensic identification. Herein, a butterfly-shaped molecule DPTS with solid fluorescence plus excited-state intramolecular proton transfer (ESIPT) properties was used to develop for enhancing the visualization of the LFPs. Considering the solid fluorescence of DPTS, the color and efficiency of DPTS with a large Stokes shift (216 nm) can be tuned by changing the morphology of its aggregates, and gradually red-shifted (green-yellow-red) with increasing water content. Furthermore, its effectiveness for the detection of LFPs was demonstrated on various different substrates including paper box, tinfoil and weighting paper. The emissive fingerprint of DPTS obtained gave good fluorescence images with high contrast and resolution such as the core, delta, bifurcation, ridge termination, independent ridge and pores. Caging of the phenol donor of DPTS with a sensitive biomarker group provided DPTS-ONOO-, which had high sensitive with detection limit of 5 nM and the quantification limit of 21 nM toward ONOO-. Modularly derived DPTS-ONOCY was synthesized and demonstrated specific fluorescence imaging of exogenous and endogenous peroxynitrite (ONOO-) in living macrophage cells.

Automated summary

The study used the butterfly-shaped molecule DPTS with solid fluorescence and ESIPT properties to enhance the visualization of latent fingerprints, showing promising results. DPTS fluorescence color and efficiency can be tuned by changing the morphology of its aggregates, demonstrating good detection of LFPs and high specificity in living cells.