A single pH fluorescent probe for biosensing and imaging of extreme acidity and extreme alkalinity

作者：Chao, Jian-Bin^*; Wang, Hui-Juan; Zhang, Yong-Bin; Li, Zhi-Qing; Liu, Yu-Hong; Huo, Fang-Jun; Yin, Cai-Xia; Shi, Ya-Wei; Wang, Juan-Juan

来源：Analytica Chimica Acta, 2017, 975: 52-60.

DOI：10.1016/j.aca.2017.04.020

• pH fluorescent probe
• Extreme acidity and alkalinity
• E. coli cells
• Bioimaging

A simple tailor-made pH fluorescent probe 2-benzothiazole (N-ethylcarbazole-3-yl) hydrazone (Probe) is facilely synthesized by the condensation reaction of 2-hydrazinobenzothiazole with N-ethylcarbazole-3-formaldehyde, which is a useful fluorescent probe for monitoring extremely acidic and alkaline pH, quantitatively. The pH titrations indicate that Probe displays a remarkable emission enhancement with a pK(a) of 2.73 and responds linearly to minor pH fluctuations within the extremely acidic range of 2.21-3.30. Interestingly, Probe also exhibits strong pH-dependent characteristics with pK(a) 11.28 and linear response to extreme-alkalinity range of 10.41-12.43. In addition, Probe shows a large Stokes shift of 84 nm under extremely acidic and alkaline conditions, high selectivity, excellent sensitivity, good water-solubility and fine stability, all of which are favorable for intracellular pH imaging. The probe is further successfully applied to image extremely acidic and alkaline pH values fluctuations in E. coli cells.

• 出版日期2017-7-4
• 单位山西大学; 中国科学院长春应用化学研究所