Ciprofloxacin-Loaded Gold Nanoparticles against Antimicrobial Resistance: An In Vivo Assessment

Area of Science:

• Nanomedicine
• Antimicrobial drug delivery
• Bacterial infection models

Background:

• Gold nanoparticles (AuNPs) are explored for drug delivery, but in vivo efficacy of drug-loaded AuNPs against tissue-resident bacteria is understudied.
• Ciprofloxacin (CIP) is a broad-spectrum fluoroquinolone antibiotic with low resistance development.
• Enterococcus faecalis infections can be challenging to treat with conventional antibiotics.

Purpose of the Study:

• To synthesize and characterize Ciprofloxacin-loaded gold nanoparticles (CIP-AuNPs).
• To evaluate the in vitro and in vivo antibacterial efficacy of CIP-AuNPs against Enterococcus faecalis.
• To assess the biocompatibility of CIP-AuNPs in a mouse model.

Main Methods:

• Synthesis and physical characterization of CIP-AuNPs.
• In vitro antibacterial assays against E. faecalis.
• In vivo studies involving tail vein administration of CIP-AuNPs in infected mice (liver and kidney colonization).
• Hemolysis assay to evaluate biocompatibility.

Main Results:

• Successfully synthesized stable CIP-AuNPs with enhanced in vitro antibacterial activity against E. faecalis compared to free CIP.
• CIP-AuNPs effectively eradicated E. faecalis from liver and kidney tissues in infected mice after eight days of treatment.
• CIP-AuNPs demonstrated non-hemolytic properties, indicating good biocompatibility.

Conclusions:

• CIP-AuNPs represent a promising and biocompatible therapeutic alternative for treating E. faecalis infections, especially those resistant to conventional drugs.
• Further investigation into CIP-AuNPs is warranted for their potential application in combating resistant bacterial infections.