具有较大Stokes位移的新型苯并噻二唑基pH荧光探针的制备及性能研究

A benzothiadiazole-based fluorescent pH probe with large Stokes shift

合成了2种基于苯并噻二唑的荧光探针C1和C2,应用于极酸性条件下pH检测。利用核磁共振氢谱仪、紫外-可见分光光度计、荧光分光光度计等对合成的荧光探针分子结构及其性能进行表征。结果表明:2种荧光探针均具有较大的斯洛克斯(Stokes)位移(>100nm),且C2具有优良的专一性和光稳定性;pH从0增加到3.04时,随着pH的升高,C2的荧光强度逐渐降低;C2探针的酸度系数为1.56,在极酸性条件下C2作为pH探针具有潜在的应用前景。

Benzothiadiazole-based fluorescent probe molecules(C1 and C2)were synthesized for pH detection under extremely acidic conditions through a simple synthesis method.The probe molecular structure was characterized by 1H-NMR.UV-Vis spectra and fluorescence spectra were used to detect its properties.The results showed that both molecules had a large Stokes shift(>100nm),and C2 had excellent specificity and light stability under strong acid condition.The titration results showed that the fluorescence intensity gradually decreased with increasing pH from 0 to 3.04.The pKa of the C2 probe was 1.56.The results indicated that C2 molecules had potential application as pH probes under extremely acidic conditions.