New Fluorescent Dye for the Detection of Zn2+ in Living Cells and Fixed Sections of the Rat Pancreas

Alexey Krinochkin; Maria Valieva; Ekaterina Starnovskaya; Nataliya Slovesnova; Artem Minin; Anna Belousova; Leila Sadieva; Olga Taniya; Albert Khasanov; Alexander Novikov; Vitaly Bruskov; Svetlana Vatolina; Dmitry Kopchuk; Pavel Slepukhin; Vladimir Sharutin; Grigory Zyryanov

doi:10.1007/s10895-024-03603-1

New Fluorescent Dye for the Detection of Zn²⁺ in Living Cells and Fixed Sections of the Rat Pancreas

J Fluoresc. 2024 Feb 13. doi: 10.1007/s10895-024-03603-1. Online ahead of print.

Authors

Alexey Krinochkin^{1

2}, Maria Valieva^{1

2}, Ekaterina Starnovskaya¹, Nataliya Slovesnova^{1

3}, Artem Minin^{1

4}, Anna Belousova⁵, Leila Sadieva⁶, Olga Taniya¹, Albert Khasanov¹, Alexander Novikov⁷, Vitaly Bruskov¹, Svetlana Vatolina¹, Dmitry Kopchuk^{1

2}, Pavel Slepukhin^{1

2}, Vladimir Sharutin⁸, Grigory Zyryanov^{1

2}

Affiliations

¹ Ural Federal University, 19 Mira Street, 620002, Yekaterinburg, Russia.
² I. Ya. Postovskiy Institute of Organic Synthesis, Ural Branch of the RAS, 22 S. Kovalevskoy Street, 620219, Yekaterinburg, Russia.
³ Urals State Medical University, 3 Repina Street, 620028, Yekaterinburg, Russia.
⁴ M.N. Miheev Institute of Metal Physics, Ural Branch of the RAS, 18 S. Kovalevskoy Street, 620108, Yekaterinburg, Russia.
⁵ Institute of Immunology and Physiology, Ural Branch of the RAS, 106 Pervomaiskaya Street, 620049, Yekaterinburg, Russia.
⁶ Ural Federal University, 19 Mira Street, 620002, Yekaterinburg, Russia. l.k.sadieva@urfu.ru.
⁷ Institute of Chemistry, Saint Petersburg State University, 7/9 Universitetskaya Nab., 199034, Saint Petersburg, Russia.
⁸ Department of Chemistry, Institute of Natural Sciences, South Ural State University (National Research University), Lenin Avenue 76, 454080, Chelyabinsk, Russia.

PMID: 38349481
DOI: 10.1007/s10895-024-03603-1

Abstract

We report the synthesis and characterization of a new 4-methoxyphenyl-2,2'-bipyridine-based ligand, such as 12, bearing dipicolylaminomethyl core as a receptor unit, as a probe for the fluorescence "turn-on" detection of Zn²⁺. Thus, in the presence of Zn²⁺ the probe 12 exhibited a fluorescence enhancement with a Stokes shift of ~ 180 nm and photoluminescence quantum yields value of ~ 1.0. In addition, 12 exhibited higher binding constant for Zn²⁺ (~ 2 × 10⁵ M^-1) with the LOD reaching the nanomolar level (~ 0.1 × 10^-9 M) compare to the previously reported probe 1. The stoichiometry and structure of the [Zn(12)]²⁺ and [Zn(1)]²⁺ complexes were supported by XRD analysis, DFT calculations and ¹H NMR experiments. It was postulated that, as a result of binding of Zn²⁺, the sample exhibited a bright "on" state via the PET-ICT processes. Molecular docking studies and confocal fluorescence microscopy experiments demonstrated that the probe 12 could be used for the fluorescence detection of Zn²⁺ not only in artificially enriched with zinc salts live cells, but also in fixed tissues with cations are in a bound state. The high binding constant of compound 12 to Zn²⁺ cation allows it to be used for the accurate localization of pancreatic beta cells (islets of Langerhans).

Keywords: 2,2’-Bipyridine; Confocal microscopy; Insulin hexamer; Rat pancreas; Sensor; Zn2+ detection.

Abstract

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