Pyrene, Anthracene, and Naphthalene-Based Azomethines for Fluorimetric Sensing of Nitroaromatic Compounds

Special attention is given to the development of rapid and sensitive detection of nitroaromatic explosives for homeland security and environmental concerns. As part of our contribution to the detection of nitroaromatic explosives, fluorescent materials (A), (B) and (C) were synthesized from the reaction of 1,2-diaminocyclohexane with pyrene-1-carbaldehyde, anthracene-9-carbaldehyde and 2-hydroxy-1-naphthaldehyde, respectively. The structures of the prepared fluorescent azomethine probes were confirmed using FTIR, H-1-NMR and C-13-NMR spectroscopies. The basis of the study is the use of the synthesized materials as fluorescent probes in the photophysical and fluorescence detection of some nitroaromatic explosives. Emission increases occurred due to aggregation caused by pi-pi stacking in synthesized azomethines. To measure the nitroaromatic detection capabilities of fluorescence probes, fluorescence titration experiments were performed using the photoluminescence spectroscopy. It was observed that compound A containing pyrene ring provided the best emission intensity-increasing effect due to aggregation with the lowest LOD value (14.96 mu M) for the sensing of 4-nitrophenol. In compounds B and C, nitrobenzene with the lowest LOD (16.15 mu M and 23.49 mu M respectively) caused the most regular emission increase, followed by picric acid.

Automated summary

To address homeland security and environmental concerns, this study focuses on the development of rapid and sensitive detection methods for nitroaromatic explosives. Fluorescent materials were synthesized and confirmed using various spectroscopy techniques. These materials were found to exhibit aggregation-induced emission enhancement, making them effective for the detection of nitroaromatic explosives. Fluorescence titration experiments demonstrated the detection capabilities of the synthesized fluorescent probes.