This study investigates the antibacterial activity of novel metal complexes synthesized using levofloxacin (LEV) as a ligand. The in vitro antimicrobial effects of these complexes were evaluated against three clinically significant bacterial strains: Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa. The synthesized copper(II), cobalt(II), and nickel(II) complexes of levofloxacin were tested using the agar well diffusion method at a fixed concentration of 35 µg/mL. The diameter of the bacterial growth inhibition zones was measured and compared to those produced by free levofloxacin and the corresponding metal salts. Results demonstrated that the metal complexes exhibited significantly enhanced antibacterial activity compared to levofloxacin alone, with the copper complex showing the highest efficacy. These findings suggest that metal complexation with levofloxacin can improve its antimicrobial potency and may serve as a promising strategy for developing more effective antibacterial agents..

Levofloxacin, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa bacteria.

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