Joy Anna Merin, Prasad Sreelakshmi Thaniparambil, Ramakrishnan Kala
Department of Applied Chemistry, Cochin University of Science and Technology, Kochi, India.
Inter University Centre for Nanomaterials and Devices, Cochin University of Science and Technology, Kochi, India.
Luminescence. 2025 Jul;40(7):e70256. doi: 10.1002/bio.70256.
The persistence and rising levels of environmental pollutants have driven the development of functional materials for their sensitive detection. Trinitrophenol (TNP), a highly toxic and explosive compound, requires urgent monitoring. In this work, a novel benzimidazole-based covalent triazine framework, CTF , was synthesized via solvothermal condensation of 1,2,4,5-benzenetetraamine tetrahydrochloride and 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine. The resulting CTF exhibited excellent selectivity towards TNP, with a low detection limit of 1.38 nM and a linear detection range from 32.15 × 10 to 4.6 × 10 M. Fluorescence quenching was attributed to a combination of inner filter effect (IFE), Förster resonance energy transfer (FRET), and photoinduced electron transfer (PET) mechanisms. To enhance practical usability, a fluorescent film was developed by incorporating the CTF into a polyvinyl alcohol (PVA) matrix. The resulting CTF-PVA film showed high flexibility, water stability, and a fast fluorescence quenching response upon TNP exposure. Furthermore, a portable device was designed for rapid and user-friendly detection of TNP based on fluorescence quenching. This dual strategy solution-phase sensing and film-based detection with a portable device offers an efficient and practical approach for detecting nitroaromatic explosives in real-world settings.
环境污染物的持续存在和含量上升推动了用于其灵敏检测的功能材料的发展。三硝基苯酚（TNP）是一种剧毒且易爆的化合物，需要进行紧急监测。在这项工作中，通过1,2,4,5-苯四胺四盐酸盐与2,4,6-三（4-甲酰基苯氧基）-1,3,5-三嗪的溶剂热缩合反应，合成了一种新型的基于苯并咪唑的共价三嗪框架CTF。所得的CTF对TNP表现出优异的选择性，检测限低至1.38 nM，线性检测范围为32.15×10至4.6×10 M。荧光猝灭归因于内滤效应（IFE）、福斯特共振能量转移（FRET）和光致电子转移（PET）机制的共同作用。为提高实际可用性，通过将CTF掺入聚乙烯醇（PVA）基质中制备了一种荧光膜。所得的CTF-PVA膜具有高柔韧性、水稳定性，并且在暴露于TNP时具有快速的荧光猝灭响应。此外，设计了一种基于荧光猝灭的便携式设备，用于快速且用户友好地检测TNP。这种双策略——溶液相传感和基于膜的便携式设备检测，为在实际环境中检测硝基芳香族炸药提供了一种高效且实用的方法。
