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Updated: Jul 28, 2025

Chemiluminescence-based Assays for Detection of Nitric Oxide and its Derivatives from Autoxidation and Nitrosated Compounds
Published on: February 16, 2022
Regulating donor-acceptor system toward highly efficient dual-state emission for sensitive response of nitroaromatic
Si-Hong Chen1, Zhao-Hua Chen1, Kai Jiang2
1School of Chemistry, South China Normal University, Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education, Guangzhou Key Laboratory of Analytical Chemistry for Biomedicine, GDMPA Key Laboratory for Process Control and Quality Evaluation of Chiral Pharmaceuticals, Guangzhou 510006, China.
New benzoxazole-based dual-state emission luminogens (DSEgens) offer enhanced sensitivity for detecting nitroaromatic explosives (NAEs). These DSEgens provide a reliable platform for visual NAEs detection in various forms, improving chemical sensing capabilities.
Area of Science:
- Materials Science
- Analytical Chemistry
- Organic Chemistry
Background:
- Dual-state emission luminogens (DSEgens) are crucial fluorophores for chemical sensing, emitting efficiently in both solution and solid states.
- Previous DSEgens for nitroaromatic explosives (NAEs) detection lacked sufficient sensitivity.
- Developing highly sensitive and stable NAEs probes remains a significant challenge in chemical sensing.
Purpose of the Study:
- To design and synthesize novel benzoxazole-based DSEgens with improved sensitivity for NAEs detection.
- To investigate the structure-property relationships governing the dual-state emission and sensing performance.
- To evaluate the practical applicability of the developed DSEgens as chemoprobes for NAEs.
Main Methods:
- Computational chemistry guided the design of benzoxazole-based DSEgens.
- Synthesis and characterization of compounds 4a-4e.
- Evaluation of photophysical properties, including dual-state emission, thermal/photostability, Stokes shift, and solvatochromism.
- Assessment of sensitivity and selectivity towards NAEs, including determination of detection limits.
- Demonstration of NAEs detection on various substrates like filter paper and film.
Main Results:
- Compounds 4a-4e exhibited desirable properties like thermal/photostability and large Stokes shifts.
- A balance between rigid conjugation and distorted conformation led to DSE properties in D-A type fluorophores.
- Compounds 4d and 4e displayed aggregation-induced emission (AIE) due to molecular conformation and restricted intramolecular rotation.
- DSEgen 4e showed high sensitivity towards NAEs with a detection limit of 10-8 M and anti-interference capabilities.
- Visual NAEs detection was achieved in solution, on filter paper, and on film.
Conclusions:
- Novel benzoxazole-based DSEgens were successfully synthesized, demonstrating enhanced performance for NAEs detection.
- The designed DSEgens offer a sensitive, stable, and visually distinct platform for NAEs chemoprobe applications.
- These findings support the potential of DSEgens as reliable tools for explosive detection and chemical sensing.
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