一种具有双重功能的可视化pH荧光探针的合成及光谱研究

以二烯单酮结构为荧光团,酚羟基为脱质子基团,合成了一种具有双重功能的可视化pH荧光分子探针.pH滴定实验表明,探针的紫外吸收和荧光光谱均对溶液的pH值有很强的依赖性,当体系溶液由酸性变为碱性时,探针的紫外吸收光谱发生明显的红移,并伴有溶液颜色的显著变化;荧光光谱强度在酸性条件下随pH值的变化不大,而在碱性条件下随pH值...

Synthesis and Spectra Properties of a Fluorescent and Colorimetric pH-Indicator

A fluorescent and colorimetric pH-indicator 1,5-bis(1-hydroxy-4-methoxphenyl)-1,4-pentadiene-3-one was synthesized based on the ketene structure as the fluorogen and phenolichydroxyl as the deprotonation group.The pH titration indicated that the probe displayed strong spectral sensitivity to pH in absorption spectra and fluorescence spectra.The absorption spectra were red-shifted and the solution undergoed distinct color changes from yellow to red with pH turning from acidity to basicity.The fluorescence spectra changed little under acidic solution,while there was more than 20-fold increase in the fluorescence emission intensity under basic solution.The fluorescence dissociation constant(pKa)was calculated to be 8.13 by using the formula of Henderson-Hasselbach,and the fluorescence quantum yield(in ethanol solution) was found to be 0.056 by comparing with the fluorescence quantum yield of quinine sulfate in 0.5 mol/L H2SO4.Furthermore,the probe also showed strong light resistant and anti-metal interference capability.