ESIPT-based fluorescent enhanced probes prompted by methylated β-cyclodextrin for the detection of thiophenols

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Vol. 302; p. 123012
• Main Authors: Peng, Hai-Yan, Zhang, Gang, Sun, Ru, Xu, Yu-Jie, Ge, Jian-Feng
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 05.12.2023
• Subjects: ESIPT; Fluorescent probe; M-β-CD; Thiophenols; Thiophenols; M-β-CD; ESIPT; Fluorescent probe
• ISSN: 1386-1425; 1873-3557
• DOI: 10.1016/j.saa.2023.123012

[Display omitted] •Probes 1a-b for detection of thiophenols by ESIPT mechanism were constructed with diethylcoumarin–salicylaldehyde units.•They showed large Stokes shift (greater than100 nm) and one of them displayed NIR-emitting (670 nm) when detecting thiophenols.•Probes 1a-b could form inclusion complexes with M-β-CD.•The presence of M-β-CD reduced the detection limits of probes 1a-b towards thiophenols. Thiophenol and its derivatives are compounds with high toxicity to organisms and environmental pollution, so it is necessary to detect the level of thiophenols in the environment and biological samples. The probes 1a-b were obtained by introducing the 2,4-dinitrophenyl ether group into diethylcoumarin–salicylaldehyde based compounds. And they can form host-guest compounds with methylated β-cyclodextrin (M-β-CD), the association constants of inclusion complexes are 49.2 M−1, 125 M−1 respectively. The fluorescence intensities of probes 1a-b at 600 nm (1a) and 670 nm (1b) increased significantly in thiophenols detection. Meanwhile, with the addition of M-β-CD, the hydrophobic cavity of M-β-CD significantly increased the fluorescence intensity of probes 1a-b, thus the detection limits of probes 1a-b to thiophenols were reduced from 410 nM, 365 nM to 62 nM, 33 nM respectively. Whereas, the good selectivity and short response time of probes 1a-b towards thiophenols was not affected in the presence of M-β-CD. Moreover, probes 1a-b were used for further water sample detection and HeLa cell imaging experiments due to their good response to thiophenols and the results suggested that probes 1a-b had the potential to detect the content of thiophenols in water samples and living cells.