Sathiyaraj Munusamy, Thiagarajan Viruthachalam
Photonics and Biophotonics Lab, School of Chemistry, Bharathidasan University Tiruchirappalli-620 024 India
Faculty Recharge Programme, University Grants Commission New Delhi India.
RSC Adv. 2020 Jul 8;10(43):25848-25855. doi: 10.1039/d0ra04941g. eCollection 2020 Jul 3.
We developed a D-π-A based unsymmetrical azine molecule 4-(()-(()-(4-(dipropylamino)benzylidene)hydrazono)methyl)benzonitrile [DPBN] and studied its optical and aggregation induced emission properties. The DPBN molecule shows good aggregation induced emission (AIE) behaviour with 1157-fold fluorescence enhancement in the aggregated state. In addition to that, both colorimetric as well as fluorometric sensing studies revealed that DPBN selectively detects diethylchlorophosphate (DCP), a potent nerve agent. Interestingly, DPBN shows solvent dependent optical output in the presence of DCP two different mechanisms. In the monomer state, it shows red shifted fluorescence enhancement along with color change from colorless to orange color the formation of a new intramolecular charge transfer state in pure tetrahydrofuran (THF). In the aggregated state, DPBN shows blue shifted emission with fluorescence enhancement in THF-water mixture by protonation at the amine nitrogen centre. Thus, DPBN can be used as a diagnostic measure to selectively detect nerve agents like DCP. This study also paves the way for further development of molecular probes for nerve agents that would represent immense implications in various fields of chemistry and biology.
我们合成了一种基于D-π-A的不对称吖嗪分子4-((((4-(二丙基氨基)亚苄基)肼基)甲基)苯甲腈[DPBN]，并研究了其光学性质和聚集诱导发光特性。DPBN分子表现出良好的聚集诱导发光(AIE)行为，在聚集状态下荧光增强1157倍。此外，比色和荧光传感研究均表明，DPBN能选择性地检测强效神经毒剂二乙基氯磷酸酯(DCP)。有趣的是，在DCP存在的情况下，DPBN根据两种不同的机制表现出依赖溶剂的光学输出。在单体状态下，在纯四氢呋喃(THF)中形成新的分子内电荷转移态，它表现出红移荧光增强以及颜色从无色变为橙色的变化。在聚集状态下，DPBN在THF-水混合物中通过胺氮中心的质子化表现出蓝移发射和荧光增强。因此，DPBN可作为一种诊断手段来选择性地检测像DCP这样的神经毒剂。这项研究也为神经毒剂分子探针的进一步发展铺平了道路，这将在化学和生物学的各个领域产生巨大影响。
