Ruthenium Complexes with Pyridazine Carboxylic Acid: Synthesis, Characterization, and Anti-Biofilm Activity

Area of Science:

• Coordination Chemistry
• Medicinal Chemistry
• Materials Science

Background:

• Antimicrobial drug resistance necessitates the development of novel antibacterial compounds.
• Metal complexes, particularly those involving ruthenium, are explored for their therapeutic potential.
• Pyridazine-3-carboxylic acid (pdz-3-COOH) serves as a ligand for creating new metal-based drugs.

Purpose of the Study:

• To synthesize and characterize novel ruthenium complexes with pdz-3-COOH.
• To evaluate the antibacterial, anti-biofilm, and anti-virulence activities of these complexes.
• To assess the safety profile and molecular interactions of the ruthenium compounds.

Main Methods:

• Synthesis and structural characterization of ruthenium complexes using spectroscopic techniques and SC-XRD analysis.
• Evaluation of anti-biofilm and anti-virulence factor production (pyoverdine) in *Pseudomonas aeruginosa* PAO1.
• Cytotoxicity assays on CHO-K1 cells, molecular docking, and fluorescence spectroscopy for HSA interaction studies.

Main Results:

• Three novel ruthenium complexes (1, 2, and 3) were successfully synthesized and characterized.
• Complexes 1 and 2 exhibited significant anti-biofilm activity against *P. aeruginosa* PAO1, surpassing the free ligand.
• Compounds 1 and 2 effectively suppressed pyoverdine production, comparable to ciprofloxacin, with no observed cytotoxicity.

Conclusions:

• The synthesized ruthenium-pdz-3-COOH complexes demonstrate promising antibacterial and anti-biofilm properties.
• These compounds represent potential therapeutic agents against bacterial infections, particularly those involving resistant strains.
• The lack of cytotoxicity suggests a favorable safety profile for further investigation.