Metallic Gallium Droplets Exhibit Poor Antibacterial Properties

Area of Science:

• Materials Science
• Nanotechnology
• Microbiology

Background:

• Antibiotic resistance necessitates novel therapeutic agents.
• Metallic nanoparticles (e.g., silver, copper, zinc) exhibit antibacterial properties via metal ion leaching.
• Gallium (Ga) compounds show antibacterial potential, leading to investigation of metallic Ga droplets.

Purpose of the Study:

• To evaluate the antibacterial efficacy of metallic Ga droplets against methicillin-resistant *Staphylococcus aureus* (MRSA) and *Pseudomonas aeruginosa* (P. aeruginosa).
• To explore the potential of functionalizing Ga droplets to enhance antibacterial activity.

Main Methods:

• Testing varying concentrations of Ga droplets against MRSA and P. aeruginosa.
• Employing galvanic replacement reactions to functionalize Ga droplets with copper and silver.
• Assessing bacterial reduction post-interaction with Ga droplets and functionalized particles.

Main Results:

• Ga droplets exhibited only modest antibacterial activity against both MRSA and P. aeruginosa, even at high concentrations (2 mg/mL).
• Functionalization of Ga droplets with copper and silver via galvanic replacement significantly enhanced antibacterial efficacy.
• Functionalized particles achieved total detectable reduction of MRSA and >96% reduction of P. aeruginosa.

Conclusions:

• Metallic Ga droplets possess limited intrinsic antibacterial activity compared to conventional antibiotics and established antibacterial nanomaterials.
• The antibacterial efficacy of Ga droplets can be substantially improved through surface functionalization with other metals like copper and silver.
• Functionalized Ga droplets represent a viable strategy for developing enhanced antibacterial agents against resistant pathogens.