2-羟基萘甲醛苯甲酰腙衍生物对Al~(3+)的裸眼识别和荧光传感

设计合成了化合物4-羟基苯甲酰-(2-羟基萘甲醛)腙(L)探针,经金属离子识别研究发现探针L对Al~(3+)具有良好的荧光增强识别效果且不受其它金属离子的干扰,且识别过程中溶液的颜色发生了明显变化,可以实现Al~(3+)的可视法检测,核磁滴定、job-plot、基质辅助激光解吸电离飞行时间质谱(MALDI-TOF)等实验结果显示,探针L与Al~(3+)以摩尔比2∶1的方式进行配位。通过对紫外滴定数据的非线性拟合分析,探针L与Al~(3+)的结合常数为1.3×10~4L/mol,最低检测限为3.71×10~(-6)L/mol。因此,该腙类衍生物作为Al~(3+)的荧光及比色探针,识别体系线性范围较宽,检测限低,在痕量Al~(3+)的检测方面具有潜在的应用价值。

“Naked-eye” and Fluorescence “Turn-on” Recognition of Al3+ Based on 2-Hydroxy-Naphthalene-Formaldehyde Benzoyl-Hydrazone Derivatives

The probe 4-hydroxy-benzoyl-(2-hydroxy-naphthalene-formaldehyde) hydrazone(L) was synthesized and evaluated. The UV-Vis and fluorescence spectra suggested that probe L has highly Al³⁺-selective affinity over others commonly coexistent metal ions by fluorescence enhancing. Meanwhile, the color change of probe L solution after addition of Al³⁺ is obvious. ¹H NMR titration, job-plot, and (MALDI-TOF) results indicate that the complex molar ratio of Al³⁺/L is 1:2. The binding constant of Al³⁺/L is calculated to be 1.3×10⁴ L/mol by nonlinear curve-fitting based on the UV-Vis titration data, and the detection limit reaches 3.71×10^-6 L/mol. The UV-Vis and fluorescence emission titration experiment show that a wide range and low detection limit can be achieved in the present sensing system. This result suggests that the probe L has potential application in determination of trace Al³⁺ ions.