A novel turn-on fluorescent probe for detection of pH in extremely acidic environment and its application

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Molecular and biomolecular spectroscopy, 2023-12, Vol.303, p.123203, Article 123203
• Main Authors: Zhou, Wu, Pan, Yuanjiang, Liu, Yuxuan, Liang, Qingxiang, Zhou, Dongkui, Wu, Aibin, Shu, Wenming, Yu, Weichu
• Format: Article
• Language: English
• Subjects: Extremely acidic environment; Fluorescent probe; Turn-on
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2023.123203

A water-soluble “turn-on” fluorescent probe PNAP based on pyrene was designed and synthesized. PNAP could detect the pH in the extremely acidic environment with high sensitivity, selectivity and good repeatability. [Display omitted] •PNAP was water-soluble and simple to synthesize.•PNAP showed remarkable turn-on fluorescence about 124-fold linearly toward pH in the range of 0.95–3.36.•PNAP exhibited high sensitivity, fast response time, strong anti-ion interference ability and good repeatability for pH.•PNAP could be used in the detection of pH in the environmental water samples and test strips. A water-soluble turn-on fluorescent probe PNAP for pH has been designed and synthesized. PNAP was consist of pyrene as fluorophore and morpholine as receptor. Owing to the photoinduced electron transfer (PET) effect, the fluorescence of PNAP was quenched, while PNAP exhibited a remarkable “turn-on” fluorescence with the increase of acidity. Notably for its pKa of 2.15, PNAP was one of the pH fluorescent probes used in extremely acidic environments. Furthermore, PNAP also displayed good repeatability, strong anti-ion interference ability, high sensitivity and selectivity toward pH. In addition, PNAP has been successfully applied to the test strips and monitor the pH of environment water samples and realistic samples, showing its good promising prospect.