In an attempt to obtain a model of copper(II) ion‐selective sensors, a new 1,8‐naphthalimide‐based fluorescence chemosensor, N ‐allylamine‐4‐[(E)‐4‐(([2‐aminoethyl]imino)methyl) benzene‐1,3‐diol]‐1,8‐naphthalimide (NABN), was designed and synthesized. The sensor NABN is fully characterized by melting point analysis, fourier transform infrared spectra, Ultraviolet–visible (UV–vis) spectra, fluorescence spectra, ¹H NMR and ¹³C NMR spectroscopy, and mass spectrometry. NABN showed an unrivaled sensing behavior and an ardent selectivity toward copper(II) ion over other competitive metal ions tested in solution (N,N‐Dimethylformamide (DMF)/Tris–HCl buffer, 1:1, v/v, pH = 7.2). The sensor showed a linear fluorescence quenching toward copper(II) ion in the range 0–50 μM, with a detection limit of 1.92 × 10⁻⁷ M estimated. Job's method indicated the formation of a 2:1 coordinative mode of the sensor with copper(II) ion with a high threshold of binding constant of 4 × 10¹² M⁻¹. Combining the above results, the quenching response of NABN toward Cu(II) ions could be ascribed to the strong, intrinsic paramagnetic behavior of Cu(II).

中文翻译：

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荧光“开-关”传感器，用于Cu2 +离子的高度选择性和灵敏检测

为了获得铜（II）离子选择性传感器的模型，一种新的基于1,8-萘二甲酰亚胺的荧光化学传感器，N-烯丙胺-4-[（E）-4-（（[2-氨基乙基]亚氨基（甲基）苯-1,3-二醇] -1,8-萘二甲酰亚胺（NABN）的设计和合成。NABN传感器具有以下特点：熔点分析，傅立叶变换红外光谱，紫外-可见（UV-vis）光谱，荧光光谱，¹ H NMR和¹³13 C NMR光谱法和质谱法。与在溶液中测试的其他竞争性金属离子（N，N-二甲基甲酰胺（DMF）/ Tris-HCl缓冲液，1：1，v / v，pH = 7.2）相比，NABN表现出无与伦比的传感行为和对铜（II）离子的强烈选择性。 ）。传感器显示出对铜离子的线性荧光猝灭，范围为0至50μM，估计检测限为1.92×10 ^-7M。乔布的方法表明，传感器与铜（II）离子形成了2：1的配位模式，结合常数的阈值很高，为4×10 ¹²  M ^-1。结合以上结果，NABN对Cu（II）离子的猝灭响应可以归因于Cu（II）的强固有固有顺磁行为。