Abstract:

A novel dual-function coumarin based fluorescent probe was prepared from 4-(diethylamino)salicylaldehyde with methyl hydrazinecarboxylate, and its structure was characterized by NMR, FTIR, and HRMS. Fluorescence emission spectra showed that in methanol solution, within 30 seconds, probe L formed a 1∶1 complex L-Cu²⁺ with Cu²⁺ which caused a fluorescence quenching effect with a quenching rate of 100%. It had good specificity for Cu²⁺ and could resist the interference of metal ions such as Ba²⁺, Li⁺, Cu⁺, Al³⁺, Zn²⁺, Cs²⁺, Mn²⁺, Ca²⁺, Hg²⁺, Cd²⁺, K⁺, Mg²⁺, Na⁺, Co²⁺, Ag⁺, Fe³⁺ and Cr²⁺. And the detection limit was as low as 1.70×10^-8mol/L with high sensitivity. Meanwhile, based on the ligand substitution principle, complex L-Cu²⁺ could be used as a fluorescence sensor to achieve fluorescence-enhanced response recognition of PO{}_{\mathrm{4}}^{\mathrm{3}-}. The process with good selectivity, could resist the interference of common anions (NO{}_{\mathrm{2}}^{-}, CO{}_{\mathrm{3}}^{\mathrm{2}-}, SO{}_{\mathrm{3}}^{\mathrm{2}-}, HPO{}_{\mathrm{4}}^{\mathrm{2}-}, P₂O{}_{\mathrm{7}}^{\mathrm{4}-},Br^-, F^-, HCO{}_{\mathrm{3}}^{-}, SO{}_{\mathrm{4}}^{\mathrm{2}-}, C₂O{}_{\mathrm{4}}^{\mathrm{2}-}, Cl^- and CH₃COO^-), and the detection limit was as low as 6.00×10^-8mol/L. In addition, probe L was successfully applied in the fields of pharmaceutical chemistry and chemical environmental protection with excellent experimental results.

Key words: coumarin, fluorescent probe, Cu²⁺, PO{}_{\mathrm{4}}^{\mathrm{3}-}, sequential recognition

摘要：

以4-二乙氨基水杨醛和肼基甲酸甲酯为原料制备一种新型双功能香豆素荧光探针L，并通过NMR、FTIR及HRMS对其结构表征。荧光发射光谱表明，在甲醇溶液中，探针L与Cu²⁺形成1∶1的络合物L-Cu²⁺，在30s时间内引起荧光淬灭效应，淬灭率近100%，且对Cu²⁺检测过程中具有良好的特异性，可抵抗Ba²⁺、Li⁺、Cu⁺、Al³⁺、Zn²⁺、Cs²⁺、Mn²⁺、Ca²⁺、Hg²⁺、Cd²⁺、K⁺、Mg²⁺、Na⁺、Co²⁺、Ag⁺、Fe³⁺及Cr²⁺等金属离子的干扰，检测极限低至1.70×10^-8mol/L，具有高度灵敏性。同时，基于配体置换原理，络合物L-Cu²⁺可作为荧光传感器实现对PO{}_{\mathrm{4}}^{\mathrm{3}-}的荧光增强响应识别，且检测过程具有良好的选择性，可抵抗常见阴离子（NO{}_{\mathrm{2}}^{-}、CO{}_{\mathrm{3}}^{\mathrm{2}-}、SO{}_{\mathrm{3}}^{\mathrm{2}-}、HPO{}_{\mathrm{4}}^{\mathrm{2}-}、P₂O{}_{\mathrm{7}}^{\mathrm{4}-}、Br^-、F^-、HCO{}_{\mathrm{3}}^{-}、SO{}_{\mathrm{4}}^{\mathrm{2}-}、C₂O{}_{\mathrm{4}}^{\mathrm{2}-}、Cl^-、CH₃COO^-）的干扰，检测限低至6.00×10^-8mol/L。此外，探针L成功应用于医药化工及化工环境保护领域，得到良好实验效果。

关键词: 香豆素, 荧光探针, 二阶铜离子, 磷酸根, 连续识别