Zinc-Based Nanoparticles Reduce the Bacterial Burden and Protect Collagen in a Mouse Cutaneous Wound Model

Area of Science:

• Materials Science
• Nanotechnology
• Microbiology

Background:

• Multidrug-resistant bacteria, especially in biofilms, pose a significant challenge to current antimicrobial treatments.
• Developing novel strategies to combat resistant bacterial infections is crucial for public health.

Purpose of the Study:

• To investigate the efficacy of zinc oxide (ZnO) and zinc sulfide (ZnS) nanoparticles (NPs) against clinically relevant bacteria.
• To evaluate their potential in combating planktonic bacteria and disrupting bacterial biofilms.
• To assess their therapeutic effect on skin wound infections and their impact on tissue integrity.

Main Methods:

• Antibacterial activity assays against planktonic bacteria and mature biofilms.
• Microscopy techniques (SEM, confocal) to visualize biofilm structural integrity.
• Gene expression analysis to understand biofilm formation interference.
• In vivo studies using a mouse skin wound infection model.

Main Results:

• Both ZnO and ZnS NPs showed antibacterial activity against planktonic bacteria, with ZnO being more potent.
• ZnS-NPs were more effective in disrupting mature biofilms by reducing metabolic activity.
• Zn-NP treatment compromised biofilm structure and downregulated key genes in *P. aeruginosa* exopolysaccharide biosynthesis.
• Topical application of Zn-NPs significantly reduced bacterial burden in mouse skin wounds.
• Zn-NPs inhibited collagen degradation and helped maintain collagen levels in wounded skin.

Conclusions:

• Zinc oxide and zinc sulfide nanoparticles demonstrate significant potential as antimicrobial agents against multidrug-resistant bacteria.
• ZnS-NPs are particularly effective in disrupting bacterial biofilms.
• Zn-NPs exhibit a dual role in wound management by reducing bacterial load and preserving tissue collagen, indicating their therapeutic value.