摘要
在振动诱导发光单元N,N’-二苯基二氢二苯并[a,c]吩嗪(DPAC)N-N轴两翼的苯环上分别引入金属离子配位基团,合成了荧光化学传感器DPAC-H-COOH,其结构采用核磁共振氢谱(1H-NMR)、碳谱(13C-NMR)及高分辨质谱进行表征,结果表明,DPAC-H-COOH通过四配位选择性结合Zn^(2+)/Cd^(2+)/Cu^(2+)3种阳离子,并与它们均以物质的量之比1∶1的方式形成分子内复合物。由于离子半径的差异以及配体-金属电子转移的作用,传感器分子与Zn^(2+)/Cd^(2+)/Cu^(2+)结合分别表现出不同的荧光信号,因此,该传感器分子不但可肉眼进行区分,还可以检测上述3种性质类似的阳离子,对Zn^(2+)、Cd^(2+)和Cu^(2+)的检出限分别为80.2 nmol/L、0.506μmol/L和0.263μmol/L,实现了采用单个传感器分子识别检测多种金属离子的功能。
N,N’-diphenyldihydrodibenzo[a,c]phenazines(DPACs)are a class of vibration-induced emission(VIE)-active molecules,which exhibit either a bent or planar configuration at the excited-state,leading to unique blue and orange-red dual fluorescence emission features.The emission color of DPAC molecules is tuned from red to deep blue by varying the degree of inhibition of the planarization processes.Based on this principle,a new fluorescent probe,DPAC-H-COOH,was designed and synthesized in this work by asymmetrically introducing metal-ion coordination groups—aniline N,N’-diacetic acid and phenoxyacetic acid ligands—onto the two“arms”of a DPAC core for chelating metal ions.DPAC-H-COOH was characterized by 1H-NMR(nuclear magnetic resonance),13C-NMR,and HRMS(high resolution mass spectrum),and the test results indicate that DPAC-H-COOH binds selectively to Zn^(2+)/Cd^(2+)/Cu^(2+)through tetra-coordination,forming intramolecular complexes in a stoichiometric ratio of 1∶1.The coordination with Zn^(2+)/Cd^(2+)limits the planarization process of the excited state of DPAC core resulting in an enhancement in blue fluorescence and decrease in orange-red fluorescence.While DPAC-H-COOH exhibits a grayish green fluorescence when coordinated with Cd^(2+),chelation with Zn^(2+)leads to a stronger enhancement in the blue fluorescence and a more thorough decrease in the red fluorescence of the probe.Moreover,due to the ligand-metal charge transfer(LMCT)when bound with paramagnetic Cu^(2+),the blue and orange-red dual fluorescence of DPAC-H-COOH are quenched simultaneously.The detection limit of the probe for Zn^(2+),Cd^(2+)and Cu^(2+)is 80.2 nmol/L,0.506μmol/L and 0.263μmol/L,respectively.This work develops a single molecular probe suitable for the detection of multiple metal ions based on the VIE mechanism.
作者
郭启超
王嘉琪
陈松阳
王巧纯
GUO Qichao;WANG Jiaqi;CHEN Songyang;WANG Qiaochun(Key Laboratory for Advanced Materials,Institute of Fine Chemicals,School of Chemistry and Molecular Engineering,East China University of Science and Technology,Shanghai 200237,China)
出处
《华东理工大学学报(自然科学版)》
北大核心
2025年第2期166-174,共9页
Journal of East China University of Science and Technology
基金
上海市科技重大专项(2018SHZDZX03)。
