Universidade Federal do Rio de Janeiro, Campus Macaé Professor Aloísio Teixeira, CEP, Macaé, RJ, 27930-560, Brazil.
Instituto de Macromoléculas, Universidade Federal do Rio de Janeiro, Cidade Universitária, CEP, Rio de Janeiro, RJ, 21941-598, Brazil.
J Fluoresc. 2021 Jan;31(1):175-184. doi: 10.1007/s10895-020-02651-7. Epub 2020 Nov 14.
This study evaluated three isoniazid-based N-acylhydrazone derivatives (HL1, HL2, and HL3) varying their substituting groups (-H, -N(CH), and -NO) as potential chemosensors for Zn ions. To this end, the absorption and emission properties of these derivatives were investigated in the presence of Zn ions. Results point to the derivative HL2 as the best chemosensor for Zn ions because of its comparatively higher sensitivity. The color of this derivative changed from colorless to strong yellow with zinc addition, as indicated by the shift in UV-vis spectrum. Moreover, HL2 was the only derivative to emit fluorescence in the presence of Zn ions, attributable to PET inhibition and bond isomerization promoted by coordination with this metal. LOD, LOQ, and binding constant values for HL2 + Zn were 0.43 μmol.l, 0.93 μmol.l, and 5.04 × 10 l.mol, respectively. The fluorescence of HL2 with other metal ions (Fe, Mg, Na, Cd, Cu, Co, Ni, Ca, and K) was also investigated. Zn yielded the best result without Cd interferences. Job's Plot showed that the stoichiometric ratio of the complex formed by HL2 and Zn ions is 2:1 (ligand:metal). The strip test with adsorbed HL2 indicated fluorescence in the presence of zinc ions under 365 nm UV irradiation.
这项研究评估了三种异烟肼基酰腙衍生物（HL1、HL2 和 HL3），它们的取代基（-H、-N(CH3) 和 -NO）不同，作为潜在的锌离子化学传感器。为此，研究了这些衍生物在存在锌离子时的吸收和发射特性。结果表明，由于其较高的灵敏度，衍生物 HL2 是检测锌离子的最佳化学传感器。该衍生物的颜色从无色变为强烈的黄色，这表明随着锌的加入，紫外-可见光谱发生了位移。此外，HL2 是唯一一种在存在锌离子时发射荧光的衍生物，这归因于与这种金属配位促进了 PET 抑制和键异构化。HL2+Zn 的 LOD、LOQ 和结合常数值分别为 0.43 μmol.l、0.93 μmol.l 和 5.04×10 l.mol。还研究了 HL2 与其他金属离子（Fe、Mg、Na、Cd、Cu、Co、Ni、Ca 和 K）的荧光。锌在没有 Cd 干扰的情况下产生了最佳结果。Job 图表明 HL2 和锌离子形成的配合物的化学计量比为 2:1（配体：金属）。吸附 HL2 的条带试验表明，在 365nm UV 照射下存在锌离子时会产生荧光。
