3rd International Conference on Chemo and BioInformatics, Kragujevac, September 25-26. 2025. (pp. 503-506)
АУТОР(И) / AUTHOR(S): Dušan S. Dimić, Stefan G. Perendija, Violeta Jevtović, Jasmina M. Dimitrić Marković, Aleksandra A. Rakić
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DOI: 10.46793/ICCBIKG25.503D
САЖЕТАК / ABSTRACT:
This study presents a comprehensive structural and computational investigation of a novel europium(III) complex coordinated with one protonated and one deprotonated pyridoxal- semicarbazone (PLSC) ligand. Europium(III) complexes are of growing interest due to their characteristic luminescent and magnetic properties, which make them promising candidates for cancer theranostic applications. The crystal structure, resolved by single-crystal X-ray diffraction (SC-XRD), reveals a nine-coordinate Eu(III) center stabilized through tridentate ONO coordination mode by both PLSC and PLSC-H ligands, a bidentate nitrate ion, and a coordinated water molecule, [Eu(PLSC)(PLSC-H)(NO₃)(H₂O)]·[NO₃]·3H₂O. Hirshfeld surface analysis and QTAIM topology analysis confirmed the presence of strong hydrogen bonding and partially covalent metal–ligand interactions. Spectrofluorimetric studies demonstrated selective binding of the complex near Trp214 in human serum albumin (HSA), and efficient intercalation into calf thymus deoxyribonucleic acid (ctDNA), displacing ethidium bromide (EtBr). Binding free energy values (ΔGb = −36.4 kJ mol⁻¹ for HSA and −21.7 kJ mol⁻¹ for ctDNA) and molecular docking simulations supported these findings, emphasizing the role of hydrogen bonding and electrostatic interactions. The mixed protonation states of the ligands contribute to fine-tuning of the coordination geometry and electronic properties. These results underscore the potential of the Eu(III)–pyridoxal-semicarbazone complex as a multifunctional agent for biomolecular recognition, targeted drug delivery, and luminescent imaging in biomedical systems.
КЉУЧНЕ РЕЧИ / KEYWORDS:
Eu(III)-pyridoxal-semicarbazone complex, SC-XRD, fluorescence spectroscopy, molecular docking, cancer theranostics
ПРОЈЕКАТ / ACKNOWLEDGEMENT:
The authors are thankful to the University of Ha’il, Kingdom of Saudi Arabia. This research was funded by the Scientific Research Deanship at the University of Ha’il, Saudi Arabia, through project number RG-24009.
ЛИТЕРАТУРА / REFERENCES:
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- S. U. Parsekar, K. Paliwal, P. Haldar, P.K.S. Antharjanam, M. Kumar., Synthesis, Characterization, Crystal Structure, DNA and HSA Interactions, and Anticancer Activity of a Mononuclear Cu(II) Complex with a Schiff Base Ligand Containing a Thiadiazoline Moiety, ACS Omega, 7(3) (2022) 2881–2896.