对Fe^3+和草酸具有荧光“关-开”功能的喹啉衍生物

Quinoline derivative with fluorescent“off-on”function for Fe and oxalic acid

通过8-羟基喹啉-2-甲醛与水杨酰肼的缩合反应合成了一种喹啉席夫碱衍生物荧光分子探针(L)。采用FTIR、1HNMR、13CNMR、ESI-MS对探针L进行了表征。利用紫外吸收和荧光光谱研究了探针L的识别性能。在二甲基亚砜中,探针L与Fe3+能够形成物质的量比1∶1型配合物L-Fe,表观结合常数为4.6×10^4 L/mol。利用该配合物的形成导致的探针荧光猝灭,能够在常见金属离子中高选择性识别Fe^3+,检出限为6.8×10^-8 mol/L。进一步以L-Fe配合物为探针,实现了对草酸的高选择性荧光增强识别,检出限为1.3×10^-7mol/L。该方法可用于菠菜中草酸的检测。

A fluorescent molecular probe(L)based derivative of quinoline Schiff base was synthesized by condensation of 8-hydroxyquinoline-2-carboxaldehyde and salicylhydrazide.Probe L was characterized by FTIR,1 HNMR,13 CNMR and ESI-MS.The recognition performance of probe L was studied by absorption and fluorescence spectra.Probe L and Fe3+could form 1∶1(molar ratio)complex L-Fe in dimethyl sulfoxide with apparent binding constant of 4.6×10^4 L/mol.Through the fluorescence quenched of probe caused by the formation of the above complex,Fe^3+could be selectively recognized in common metal ions,and the detection limit was 6.8×10^-8 mol/L.Furthermore,complex L-Fe was used as a probe to achieve highly selective fluorescence enhanced recognition of oxalic acid,and the detection limit was 1.3×10^-7 mol/L.This method can be used to detect oxalic acid in spinach.