Department of Chemistry, National Institute of Technology Uttarakhand, Srinagar, Uttarakhand, India.
Department of Chemistry, Institute of Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India.
Luminescence. 2023 Jul;38(7):1199-1205. doi: 10.1002/bio.4318. Epub 2022 Jul 7.
A new fluorescent zinc (II) complex-based probe 1 encompassing a Schiff's base (E)-2-methoxy-6-((2-[5-nitropyridin-2-ylamino]ethylimino)methyl)phenol (HL) was designed, synthesized, and used for the highly selective detection of Cu . Ligand HL and complex 1 were characterized using various spectroscopic techniques such as H, C-NMR, and FTIR spectroscopy, high-resolution mass spectronomy (HRMS), UV/visible light spectroscopy, and fluorescence studies. Ligand HL did not exhibit any considerable change in fluorescence in the presence of various cations. Notably, its Zn(II) complex 1 exhibited highly selective 'TURN-OFF' fluorescence signalling towards Cu that remained uninterrupted with competing analytes. Probe 1 interacted with Cu in 1:2 (1:Cu ) stoichiometry as estimated through a Job's plot. Moreover, the selectivity of 1 was further confirmed through the interaction of the 1 + Cu complex with some possible interfering metal ions inducing an insignificant response. Additionally, the association and quenching constant were determined to be 3.30 × 10 M and 0.21 × 10 M through the Benesi-Hildebrand method and Stern-Volmer plot, respectively.
一种新的基于荧光锌（II）配合物的探针 1 被设计、合成，该探针包含席夫碱（E）-2-甲氧基-6-((2-[5-硝基吡啶-2-基氨基]乙基亚氨基)甲基)苯酚（HL），并用于高选择性检测 Cu 。使用各种光谱技术（如 H、C-NMR 和 FTIR 光谱、高分辨率质谱（HRMS）、紫外/可见光谱和荧光研究）对配体 HL 和配合物 1 进行了表征。配体 HL 在存在各种阳离子时，其荧光没有发生明显变化。值得注意的是，其 Zn(II)配合物 1 对 Cu 表现出高度选择性的“关闭”荧光信号，不受竞争分析物的干扰。通过 Job 图估计，探针 1 与 Cu 以 1:2（1:Cu）的化学计量比相互作用。此外，通过 1+Cu 配合物与一些可能的干扰金属离子的相互作用，进一步证实了 1 的选择性，这导致响应不明显。此外，通过 Benesi-Hildebrand 方法和 Stern-Volmer 图分别确定了 3.30×10 M 和 0.21×10 M 的结合常数和猝灭常数。
