Halogenated Schiff base complexes: A new type of molecular probe for specific detection of o-Nitrophenol

o-Nitrophenol (2-NP) is common nitroaromatic (NACs) explosion-prone chemical and environmental pollutant. Due to the similarities in structure and composition of nitroaromatic compounds, it is difficult to distinguish 2-NP from other NACs by conventional probes. Hence, there is an urgent need to develop a simple and fast method for 2-NP trace detection. Herein, we report a new molecular fluorescent sensor constructed from the halogenated Schiffbase complex [Zn(3Br5Cl-salpn)(H2O)(2)] (Zn-chi-L). Identifiability analysis revealed that Zn-chi-L can be used as a highly selective and sensitive molecular sensor for 2-NP, and the fluorescence signal can rapidly identify 2-NP and distinguish 2-NP from other nitroaromatics at a detection limit of (LOD) of 2.20 mu M with a response speed of less than 15 s. Unexpectedly, compared with conventional NACs probes, the fluorescence signal of Zn-chi-L is not affected by solvents, which intensity remained essentially constant in the solvents of different polarities. Based on the experimental data, the potential roles of the halogenated ligands, as well as the coordination water molecules in improving the sensitivity and specificity are discussed in detail. (c) 2023 Elsevier B.V. All rights reserved.