香豆素类荧光增强型Cu2+荧光分子探针

Fluorescence-enhancement Probe for Cu2+ Based on Coumarin

摘要:

设计合成了含酰肼和亚胺结构的双香豆素类Cu2+荧光分子探针CCu. 其结构用1HNMR、IR、HRMS和元素分析进行了表征，并考察了其光谱性能。CCu在常见碱金属离子(K+, Na+) 、碱土金属离子 (Ca2+, Mg2+) 、过渡金属及重金属离子(Cd2+, Ag+, Fe3+, Pb2+, Hg2+, Cr3+, Co2+, Ni2+, Cu2+, Zn2+) 中能够专一性的识别Cu2+。 滴加Cu2+后引起吸收光谱蓝移38nm，荧光光谱蓝移17nm，荧光增强8.2倍，溶液荧光由无色变为蓝色。CCu对pH不敏感具有较低的pKa值（3.32 ± 0. 07），可在近中性和弱碱性范围内对Cu2+进行检测。

Abstract:

A fluorescent molecular probe CCu for Cu2+ based on biscoumarin bearing hydrazide and imine unit was designed and synthesized. The structure of CCu was identified by 1HNMR, IR, HRMS and elemental analysis, and the spectral properties of CCu was investigated. CCu exhibited Cu2+-only sensitive among metal ions such as alkali (K+, Na+), alkaline earth (Ca2+, Mg2+), and transition metal ions (Cd2+, Ag+, Fe3+, Pb2+, Cr3+, Co2+, Ni2+, Cu2+, Zn2+). The addition of Cu2+ led to a 38 nm blue-shift in absorbance maximum, a 17 nmblue-shift in fluorescence maximum , a 8.2-fold fluorescence enhancement and an obvious fluorescence change from almost colorless to blue. CCu was pH-insensitive Cu2+ fluorescent probe with the pKa of 3. 32 ± 0. 07, which could be used for Cu2+ detection in neutral and weakly alkaline pH span.