Imidazo-pyridine-based zinc(II) complexes as fluorescent hydrogen sulfide probes

Dalton Trans. 2021 Nov 30;50(46):17075-17085. doi: 10.1039/d1dt02489b.

Abstract

In this work we explore the interaction of HS- with a family of fluorescent zinc complexes. In particular we selected a family of complexes with N,O-bidentate ligands aiming at assessing whether the zinc-chelating ligand plays a role in influencing the reactivity of HS- with the complexes under investigation. Different experiments, performed by diverse spectroscopic techniques, provide evidence that HS- binds the zinc center of all the complexes included in this study. The results highlight the potential of the devised systems to be used as HS-/H2S fluorescent sensors via a coordinative-based approach. To shed light on the species formed in solution when HS-/H2S interacts with the title complexes and aiming to rationalize the photophysical properties of the sensing constructs, we performed a computational analysis based on the time dependent density functional theory (TD-DFT). Preliminary bio-imaging experiments were also performed and the results indicate the potential of this class of compounds as probes for the detection of H2S in living cells.

MeSH terms

  • Coordination Complexes / chemical synthesis
  • Coordination Complexes / chemistry*
  • Density Functional Theory
  • Fluorescent Dyes / chemical synthesis
  • Fluorescent Dyes / chemistry*
  • Hep G2 Cells
  • Humans
  • Hydrogen Sulfide / analysis*
  • Imidazoles / chemistry*
  • Microscopy, Fluorescence
  • Molecular Structure
  • Pyridines / chemistry*
  • Tumor Cells, Cultured
  • Zinc / chemistry*

Substances

  • Coordination Complexes
  • Fluorescent Dyes
  • Imidazoles
  • Pyridines
  • imidazole
  • Zinc
  • pyridine
  • Hydrogen Sulfide