New phosphotetradecavanadate hybrids: crystal structure, DFT analysis, stability and binding interactions with...

Area of Science:

• Inorganic Chemistry
• Materials Science
• Biochemistry

Background:

• Polyoxometalates (POMs) are versatile inorganic clusters with diverse applications.
• Keggin-type polyoxidovanadates are of particular interest due to their unique structural and electronic properties.
• Understanding the interactions of novel POMs with biological macromolecules is crucial for developing new therapeutic or diagnostic agents.

Purpose of the Study:

• To synthesize and characterize two novel bicapped Keggin polyoxidovanadates with organic cations.
• To investigate the structural, electronic, and photophysical properties of these novel compounds.
• To explore the interactions of these polyoxidovanadates with biological macromolecules like bovine serum albumin and calf-thymus DNA.

Main Methods:

• Synthesis and isolation of novel polyoxidovanadates.
• Characterization using elemental analysis, powder X-ray diffraction, FTIR, UV-vis, NMR (51V, 31P, 13C, 1H), and fluorescence spectroscopy.
• Single-crystal X-ray diffraction, Hirshfeld surface analysis, DFT calculations, and biomolecular interaction studies (BSA and ctDNA).

Main Results:

• Two novel bicapped Keggin polyoxidovanadates, (C6H8N)5[H4PV14O42]·5H2O (1) and (C6H14N4)2(NH4)[H4PV14O42]·11H2O (2), were successfully synthesized and structurally confirmed.
• Hirshfeld surface analysis revealed dominant O⋯H/H⋯O, O⋯O, and H⋯H intermolecular interactions.
• DFT calculations confirmed protonation sites and predicted pKa values, indicating favorable molecular reduction in protonated PV14 anions. Interaction studies showed fluorescence quenching of BSA and spectral changes in ctDNA upon addition of the compounds.

Conclusions:

• The synthesized polyoxidovanadates exhibit well-defined structures and intermolecular interactions.
• The compounds demonstrate significant interactions with bovine serum albumin and calf-thymus DNA, evidenced by fluorescence quenching and spectral changes.
• These findings highlight the potential of novel polyoxidovanadates as functional materials for biological applications.