Water-stable Nickel-Based Coordination Polymer for Selective and Sensitive Enhancing and Quenching Fluorescence Sensing of Ascorbic Acid and Acetylacetone

The novel Ni-based coordination polymer [Ni(H2edda) (bpe)] (CP 1 ) was successfully synthesized by em-ploying 5,5 ' (ethane-1,2-diylbis(oxy)) diisophthalic acid (H4edda) and 1,2-bis (4-pyridyl) ethylene (bpe) under hydrothermal conditions. Structural analysis indicates that CP 1 presents a 2-fold-interpenetrated two-dimensional (2 D) framework with a uninodal sql topology. Further investigation reveals that the newly obtained CP can be stable in water or even exposed in a certain acid/base aqueous solution (pH = 3-11) for a long period of time. Remarkably, CP 1 can further serve as a bifunctional sensor for ascorbic acid (AA) and acetylacetone (acac) in aqueous media according to fluorescence enhancing and quenching effects, respectively. Notably, both sensing processes are labeled with exceptional anti -interference property, high sensitivity and selectivity, wide linear range (0-50 mu M for AA and 0.2-1.8 mM for acac) and low detection limit (1.37 nM for AA and 1.58 mu M for acac). Theoretical simulations and ex-perimental findings point out that in the process of AA detection by CP 1 , the significant fluorescence enhancement could be caused by the photo-induced electron transfer (PET) process, while the inner fil-ter effect (IFE) mechanism combined with PET should be responsible for the fluorescence quenching of CP 1 by acac.(c) 2022 Elsevier B.V. All rights reserved.