Title:An Interesting Small Molecule Fluorescent Probe for A Narrow Range
(12.5~13) pH and DMSO Detection
Volume: 19
Issue: 12
Author(s): Di Yang, Xue-Wen Diao, Ji Liu, Ya-Xin Chen, Ying-Chun Luo and Xiao-Hua Cai*
Affiliation:
- School of Chemical Engineering, GuizhouMinzu University, Guizhou, Guiyang 550025, P.R. China
Keywords:
2-Hydroxy-1-naphthylformaldehyde, malononitrile, fluorescent probe, pH monitoring, DMSO detection, probe L.
Abstract:
Aims: The development of a sensitive and visual analytical method for detecting and monitoring
the change of pH has always attracted great interest because it plays a significant role in chemical
reactions, environmental monitoring, and biological systems.
Methods: In this paper, a simple condensation reaction from readily available substrates 2-hydroxy-1-
naphthylaldehyde and malononitrile has been carried out to produce probe L with good aggregationinduced
luminescence, and its chemical structure was confirmed by 1H NMR, 13C NMR and ESI-MS.
Objective: There is a conjugated system containing two electron-withdrawing cyano groups and an electron-
donating hydroxyl group in probe L's molecular structure, exhibiting obvious fluorescence intensity
and visible color change through intramolecular charge transfer (ICT) under different pH conditions.
Results: Probe L assumes excellent fluorescence intensity in a DMF/H2O (1:9, v:v) mixed solvent system,
and exhibits good reversibility in a very narrow range of pH values (pH = 12.5~13). In addition,
probe L can also selectively identify solvent DMSO by the induction of fluorescence quenching.
Conclusion: Probe L can be used for the analysis and visual detection to pH change in DMF/H2O system,
and it may also be used as the indicator for the detection and monitoring of trace amounts of DMSO.