Biomolecular interaction studies of new transition metal(II) complexes of 4-amino-3-hydroxynaphthalene-1-sulfonic acid derived Schiff base ligand

To enhance the pharmacological properties of Schiff base ligands and minimize cytotoxicity, the use of biocompatible metal ions offers a strategic approach for improving therapeutic outcomes. This study focuses on the synthesis and characterization of Schiff base ligand and its Cu(II), Co(II) and Zn(II) metal complexes as potential chemotherapeutic agents. Comprehensive spectro-analytical techniques including FTIR, UV-Vis, ESI-Mass, XPS, and NMR spectroscopy confirmed the structural integrity and purity of these compounds. To assess their therapeutic potential, fluorescence spectral titrations with cancer biomolecules and computational simulations were performed. Further characterization included fluorescence quenching studies with serum albumin, indicating robust interactions with Stern-Volmer constants of 3.07 × 10 4 M −1 for IANS-Cu, 5.14 × 10 4 M −1 for IANS-Co, and 2.34 × 10 4 M −1 for IANS-Zn. In DNA binding studies using ethidium bromide displacement assays, the complexes demonstrated interactions via electrostatic and groove binding mechanisms, with IANS-Co displaying the highest affinity. Molecular docking studies against Human Epidermal Growth Factor Receptor-2 and Poly (ADP-ribose) Polymerase 2 revealed notable binding affinities, particularly for IANS-Co, which exhibited significant interactions with binding sites relevant to breast cancer, thus presenting a promising candidate for targeted anticancer therapies. Overall, this study highlights the significance of incorporating biocompatible metal ions into Schiff base frameworks to develop multifunctional metal complexes with improved biomolecular affinity and potential anticancer activity. The combined experimental and computational findings demonstrate that the synthesized complexes, especially IANS-Co, represent promising candidates for the development of targeted metal-based chemotherapeutic agents.