Non-covalent binary sensing platform for ratiometric and colorimetric detection of sulfide anion in aqueous solution and human urine

• Published in: Journal of photochemistry and photobiology. A, Chemistry. Chemistry., 2019-10, Vol.383, p.111995, Article 111995
• Main Authors: Li, Yanping, Fan, Junmei, Yan, Sisi, Gao, Zhipeng, Tang, Qiuping, Liu, Fengyi, Ding, Liping
• Format: Article
• Language: English
• Subjects: Anion; Anions; Aqueous solutions; Chemical compounds; Colorimetry; Coumarin; Covalence; Emission spectra; Fluorescence; Fluorophores; Human wastes; Hydroxyl groups; Pyronine; Ratiometric sensor; Selectivity; Sensitivity; Sulfide; Sulfides; Urine
• ISSN: 1010-6030; 1873-2666
• DOI: 10.1016/j.jphotochem.2019.111995

[Display omitted] •A ratiometric and colorimetric sensor for S2− was prepared simply by mixing two easily obtained fluorophores.•The sensor can sensitively detect sulfide anion in aqueous solution with a detection limit of 96 nM.•The hydroxyl group in the coumarin fluorophore was found to be reactive with sulfide anion for the sensitive sensing.•The sensor can also selectively detect sulfide in biological fluid like human urine. A ratiometric and colorimetric sensor platform for detection of sulfide anion with high sensitivity was developed by using non-covalent dual fluorophores in water and 10% human urine. In water, the constructed non-covalent coumarin/pyronine dual-fluorophore system exhibits an inherent emission of the pyronine unit at ca. 564 nm and a much weaker blue emission of coumarin unit at ca. 446 nm. The encounter with sulfide anion and its hydrolysis products elicit an increase in the blue emission of the coumarin moiety and a concomitant decrease of pyronine emission. The enhanced emission of coumarin unit was found due to the deprotonation of the hydroxyl group in coumarin by sulfide anion. The ratiometric response empowers the non-covalent sensor system a high sensitivity to sulfide anion with a detection limit of 96 nM. The remarkable ratiometric and colorimetric responses of the binary sensing system to sulfide anion was also obtained in 10% human urine and the selectivity is improved among PO43−, CO32− and OH−.