Eswaran Rajendran, Selvaraj Loganathan, Ramasamy Santhiya, Gandhi Sivaraman, Muthu Seenivasa Perumal
Department of Chemistry, The Gandhigram Rural Institute - Deemed to be University, Gandhigram, Dindigul, Tamilnadu, 624302, India.
J Fluoresc. 2025 Jul;35(7):5769-5780. doi: 10.1007/s10895-024-03925-0. Epub 2024 Oct 1.
Nitroaromatic compounds are highly explosive and illegitimate substances. Over a decade, chemists have been affianced in extensive research on the selective and sensitive detection of these nitroaromatic explosives for homeland security and environmental protection. The benzodiazepine-based enaminone (BDE) receptor has been synthesized by aqueous extract of onion catalyzed three-component reaction between o-phenylenediamine, dimedone with an aldehyde. The BDE probe is well analyzed and applied to a sensor that selectively detects picric acid (PA). UV-Vis and fluorescence spectroscopy were used to investigate the photophysical responses of the receptor (BDE). From the observed results BDE found turn-off fluorescence with the addition of picric acid and the lowest limit of detection and limit of quantification was achieved about 24.6 nM and 73.8 nM. The fluorescence quantum yield was attained about 0.28. The BDE-PA adduct formation was confirmed by H NMR titration analysis. The Job's plot analysis was performed through H NMR titrations and established the binding stoichiometry ratio of the BDE-PA adduct as 1:1 ratio. Further, DFT calculations supported the observed photophysical responses of BDE-PA adduct to confirm the molecular level interactions. The receptor was effectively applied to approximate level of picric acid in real water sample analysis.
硝基芳香族化合物是极具爆炸性的非法物质。十多年来，化学家们一直致力于对这些硝基芳香族爆炸物进行选择性和灵敏检测的广泛研究，以保障国土安全和环境保护。基于苯二氮䓬的烯胺酮（BDE）受体是通过洋葱水提取物催化邻苯二胺、二甲基酮与醛之间的三组分反应合成的。对BDE探针进行了充分分析，并将其应用于选择性检测苦味酸（PA）的传感器。利用紫外-可见光谱和荧光光谱研究了受体（BDE）的光物理响应。从观察结果来看，加入苦味酸后BDE的荧光猝灭，检测限和定量限分别达到约24.6 nM和73.8 nM。荧光量子产率约为0.28。通过1H NMR滴定分析证实了BDE-PA加合物的形成。通过1H NMR滴定进行了Job曲线分析，确定BDE-PA加合物的结合化学计量比为1:1。此外，密度泛函理论计算支持了观察到的BDE-PA加合物的光物理响应，以确认分子水平的相互作用。该受体有效地应用于实际水样分析中苦味酸的近似含量测定。
