Targeting ESKAPE pathogens with ZnS and Au@ZnS Core-Shell nanoconjugates for improved biofilm control.

Area of Science:

• Nanotechnology
• Materials Science
• Infectious Diseases

Background:

• Antibiotic-resistant infections and biofilm formation on medical implants are critical global health concerns.
• ESKAPE pathogens, including Acinetobacter baumannii and Staphylococcus aureus, pose significant threats.
• There is an urgent need for novel anti-biofilm strategies to combat these infections.

Purpose of the Study:

• To synthesize and evaluate zinc sulfide quantum dots (ZnS QD) and Au@ZnS nanoconjugates (Au@ZnS NC).
• To determine the antibacterial and anti-biofilm efficacy of these nanomaterials against a panel of ESKAPE pathogens.
• To investigate the mechanism of action of Au@ZnS NC in inhibiting biofilm formation.

Main Methods:

• Synthesis of ZnS QD and Au@ZnS NC.
• Minimum Inhibitory Concentration (MIC) assays, tube dilution, and biofilm formation assays.
• Cell permeability assays, reactive oxygen species analysis, and comet assays were used to elucidate the mechanism of action.

Main Results:

• Au@ZnS NC demonstrated significant reduction in biofilm formation and extracellular polymeric substances (EPS) production.
• Au@ZnS NC induced oxidative stress, destabilized bacterial cell structure, and caused DNA strand breakage.
• Au@ZnS nanoconjugates inhibited biofilm formation within 24 hours across all tested strains, outperforming ZnS QD and showing minimal colonization on treated urinary catheters.

Conclusions:

• Au@ZnS nanoconjugates exhibit potent antibacterial and anti-biofilm properties.
• These nanoconjugates offer a promising therapeutic strategy for controlling infections associated with medical devices and implants.
• The findings highlight the potential of Au@ZnS NC to address the challenge of biofilm-forming pathogens in healthcare settings.