色酮衍生席夫碱镁离子荧光探针的制备与表征

摘要

In this article,a chromone-derived Schiff-base ligand L called 6-hydroxy-3 formylchromone nicotinic hydrazone has been designed,synthesized and evaluated as a Mg2+ ratiometric fluorescent probe.The structure of this ligand L was confirmed by IR,NMR and its optical properties were investigated in DMSO.The results show that there is a weak fluorescence emission peak at 431 nm.The presence of Mg2+ could reduce the fluores cence emission intensity and generate a new strong fluorescence emission peak at 529 nm.Moreover,the detection of Mg2+ by L was not interfered with other common competing metal ions.The detection limit of ligand L for sensing Mg2+ was 9.16 × 10-7 mol/L and the binding constant concentration of L with Mg2+ was 5.65×10-8 mol/L.This ligand L was coordinated with Mg2+ (mole ratio of 1 ∶ 1) to form a complex (L-Mg),which was attributed to the inhibition of the photo-induced electron-transfer (PET) phenomenon.%通过6-羟基-3-甲酰基色酮和烟酸酰肼的缩合反应,合成了一种新型席夫碱配体6-羟基-3-甲酰基色酮-(烟酸酰基)腙(L)并对其与镁离子配位的荧光探针的性能进行研究利用荧光光谱、核磁共振氢谱、红外光谱等方法对该荧光探针分子的结构进行表征和荧光性能进行探究.结果表明,该配体在431 nm处具有较弱的荧光发射峰,镁离子的加入会使431 nm处的荧光发射强度降低,而在529 nm处产生一个新的很强的荧光发射峰,但该配体对其它金属离子无明显的荧光响应;经计算,其检测限可达到9.16×10-7 mol/L,结合常数为5.65×10-8 mol/L.该配体与镁离子之间形成配位比为1∶1的配合物(L-Mg)其对镁离子的识别机理是基于光诱导电子转移(PET)现象.