SYNTHESIS, CHARACTERIZATION, PREPARATION AND EVALUATION OF THE BACTERICIDAL POTENTIAL OF TWO Co+2 COMPLEXES USING LIGANDS 4-AMINOPYRIDINE AND 2,2'-BIPYRIDINE

Abstract

Background: The growing interest in organic-inorganic compounds is motivated by the unique advantages these materials offer. Combining organic and inorganic elements enables the creation of structures with varied geometries, paving the way for a wide range of coordination possibilities and directed self-assembly. Aims: To synthesize and characterize by spectroscopic techniques and thermal analysis new Co+3 compounds coordinated with 4-aminopyridine; 2,2'-bipyridine and evaluate their bactericidal potential against two distinct bacterial strains: Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Method: In this study, we report the synthesis route and characterization of the complexes by FTIRmed spectroscopy and TG/DSC thermal analysis, and the obtained complexes have the stoichiometry [Co(NH3)4(bipy)]Cl3.½H2O and [Co(NH3)4(4-apy)] Cl3.½ H2O. Results: The synthesis methodology of cobalt complexes with the ligands 4-aminopyridine and 2,2’-bipyridine proved effective, resulting in the formation of desired precipitates. The thermogravimetric analysis provided insights into the thermal properties of the complexes, indicating stability within certain temperature ranges. Mid-infrared spectroscopy allowed for the structural characterization of the complexes, highlighting characteristic shifts in the bonds of the coordinated ligands. Discussions: Evaluation of the bactericidal activity of the complexes yielded promising results, underscoring the importance of compound solubility. The complex [Co(NH3)4(bipy)]Cl.½H2O exhibited efficacy in bactericidal inhibition, particularly against the S. aureus strain. These findings emphasize the relevance of solubility and chemical composition in the antimicrobial activity of the complexes. Furthermore, the results contribute to the advancement of coordination chemistry and its potential applications, particularly in pharmacology. Conclusions: These biological activity tests revealed significant activity of the complexes against both bacterial strains. This suggests that these complexes have the potential to inhibit the growth and proliferation of these bacteria, indicating their usefulness as effective antimicrobial agents.