含吲哚和喹啉的荧光探针的合成及离子识别性能

Synthesis and Ion Recognition Properties of Fluorescent Probes Containing Indole and Quinoline

铜离子(Cu^(2+))和锰离子(Mn^(2+))在环境中分布广泛,也是生物体中重要的微量元素。目前能同时检测此两种金属离子的分子探针较少。将8-羟基喹啉-2-甲醛与吲哚-2-甲酸乙酯衍生物进行缩合,合成了两种新型的探针分子N′-[(8-羟基-2-喹啉基)亚甲基)]-1H-吲哚-2-甲酰肼和5-氯-N′-[(8-羟基-2-喹啉基)亚甲基]-1H-吲哚-2-甲酰肼,采用1H和13C核磁共振波谱法(NMR)、高分辨质谱(HRMS)和红外光谱(IR)法对新中间体及探针分子的结构进行了表征。通过荧光和紫外光谱法研究了两种探针识别Cu^(2+)和Mn^(2+)的性能,结果表明探针在二甲基亚砜溶液中对Cu^(2+)和Mn^(2+)表现出快速、灵敏的荧光淬灭响应效果,检测限低于0.5μmol/L。通过IR、HRMS和荧光可逆性实验对结合机理进行了初步探究,提出了可能的配合方式。该方法可用于环境或工农业样品中Cu^(2+)和Mn^(2+)的快速识别和检测。

Both copper ions(Cu^(2+))and manganese ions(Mn^(2+))are significant trace elements present in living organisms and widely distributed in the environment.Currently,there is a limited selection of molecular probes available for the simultaneous detection of both metal ions.In this study,two new probe molecules,N′-[(8-hydroxyquinolin-2-yl)methylene]-1 H-indole-2-carbohydrazide and 5-chloro-N′-[(8-hydroxyquinolin-2-yl)methylene]-1 H-indole-2-carbohydrazide,were synthesized by condensing ethyl indole-2-carboxylate derivatives with 8-hydroxyquinoline-2-carboxaldehyde.The structures of the new intermediates and probe molecules were characterized using various techniques,including 1H and 13 C nuclear magnetic resonance spectroscopy(NMR),high-resolution mass spectrometry(HRMS),and infrared spectroscopy(IR).The performance of the two probes in recognizing Cu^(2+)and Mn^(2+)was investigated using fluorescence and UV spectroscopy.The results demonstrated that these probes exhibited a rapid and sensitive fluorescence quenching response against Cu^(2+)and Mn^(2+)in DMSO solution,with a detection limit of less than 0.5μmol/L.The binding mechanism was preliminarily investigated using IR,HRMS,and fluorescence reversibility experiments,and the possible complexation modes were proposed.These methods hold the potential for rapid identification and detection of Cu^(2+)and Mn^(2+)in environmental,industrial,and agricultural samples.