Modern development of medicine, molecular biology and genetics is closely related to the improvement of methods for visualization of molecular processes occurring in the cells of living organisms. The fluorescence microscopy method, which provides high spatial resolution and good sensitivity, is particularly promising in this direction. Taking into account the instrumental capabilities and specificity of research objects, many commercial fluorophores based on organic dyes do not meet the high requirements of modern diagnostics, among which the most important are: ensuring specific binding to the target molecule, organelle or cell; high emission efficiency combined with photostability. In addition to the above-mentioned requirements, in the last decade the demand for phosphors sensitive to specific targets: biometals, pH of the medium, biomarkers has increased. The high luminescent activity of azomethine bases in the presence of zinc ions, combined with stability in solutions, sensitivity to the pH of the medium and observed two-photon luminescence, makes the proposed compounds ideal candidates for use in bioimaging. Zinc belongs to the group of trace elements, its uniqueness lies in the fact that it is a part of more than 300 enzymes and performs a variety of physiological functions, has antioxidant properties. Its toxicity for animals and humans is small — this is due to the fact that in excessive intake it is excreted by the body. Thus, zinc complexes luminescent in the visible region are promising dyes for biovisualization. A luminescent zinc complex based on azomethine “salen-like” ligand, which represents two molecules of 3-methyl-1-phenyl-4-formylpyrazol-5-one “cross-linked” by a molecule of propane-1,3-diamine, has been synthesized and studied. The composition and structure of the complex was established by elemental, thermogravitetric analysis and IR spectroscopy. The molecular structure of the complex was established on the basis of PCA data. The complex exhibits intense photoluminescence in solutions and can be used for visualization of cellular structures of A. cepa epidermis cells.
luminescence, zinc, bioimaging.
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