Phototriggered Biofilm Nanodisruptor with Genetic Modulation for Treating Drug-Resistant Bacterial Infections

Area of Science:

• Biomaterials Science
• Nanotechnology
• Infectious Diseases

Background:

• Biofilm-associated bacterial infections present significant challenges due to high antibiotic resistance.
• Existing treatments often struggle to penetrate the complex biofilm matrix.

Purpose of the Study:

• To develop a carrier-free nanocomposite (SPX-ICG) for enhanced biofilm eradication.
• To create a triple-mode antibacterial system integrating photothermal, photodynamic, and antibiotic therapies.

Main Methods:

• Self-assembly of sparfloxacin (SPX) and indocyanine green (ICG) into a nanocomposite (SPX-ICG).
• Utilizing near-infrared irradiation to trigger SPX-ICG disassembly and therapeutic cascade.
• Transcriptomic analysis to investigate the impact on bacterial gene expression.
• In vivo studies in infected mouse models to evaluate therapeutic efficacy.

Main Results:

• SPX-ICG demonstrated synergistic photothermal and photodynamic effects, enhancing biofilm permeability and bacterial killing.
• Transcriptomic analysis revealed downregulation of quorum sensing and signal transduction genes.
• Successful eradication of *Staphylococcus aureus* (including SPX-resistant strains) in vivo.
• Observed enhanced wound healing with minimal systemic toxicity.

Conclusions:

• The SPX-ICG nanocomposite offers a promising, minimalist approach for treating biofilm-associated infections.
• This triple-mode therapy effectively combats antibiotic-resistant bacteria and improves clinical outcomes.
• Potential application in managing severe skin and soft tissue infections.