Chemical Synthesis and Characterization of Lanthanum(III) 2-Hydroxybenzoate and Its Antibacterial Potential: <i>In Vitro</i> and <i>In Silico</i> Approaches

High Resolution Image Download MS PowerPoint Slide A novel lanthanum(III) salicylate complex (La(Sa) 3 ) with potential biomedical applications was chemically synthesized via the reaction of salicylic acid (SA) with lanthanum oxide nanoparticles (La 2 O 3 NPs). This two-step synthesis approach involved the initial preparation of La 2 O 3 NPs followed by their coordination with mixed SA ligands, after which the resulting complex and its precursors were comprehensively characterized. The structure of the La(Sa) 3 complex was investigated using nuclear magnetic resonance (NMR) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, field-emission scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM). Molecular docking studies of the newly synthesized complex were conducted to elucidate the interactions between La(Sa) 3 and the target microbial protein at the molecular level. Comparative evaluations of the bacteriostatic and bactericidal activities of the La(Sa) 3 complex, its ligand (SA), and La 2 O 3 NPs were performed against Gram-positive and Gram-negative bacteria. These studies demonstrated that the La(Sa) 3 complex exhibited significant antibacterial activity against the selected bacterial strains. The results further indicated that La(Sa) 3 showed enhanced antibacterial properties due to a synergistic effect with La 2 O 3 NPs. The morphology of the La(Sa) 3 complex revealed that the chemical synthesis of the La(Sa) 3 complex in the presence of La 2 O 3 NPs resulted in notable differences in powder and particle morphology. Spectral analyses confirmed that the synthesized La 2 O 3 NPs successfully reacted with SA to form La(Sa) 3 complex molecules. The data obtained from the in silico studies were consistent with the results of the experimentally conducted antibacterial assays. The experimental study results suggest that the La(Sa) 3 complex may be developed as a promising antibacterial drug candidate.