Broad-spectrum nanoparticles against bacteriophage infections

Area of Science:

• Biotechnology
• Nanotechnology
• Microbiology

Background:

• Bacteriophage infections pose a significant threat to bacteria-based bioreactors in the biotechnology industry.
• Over 70% of biotechnology companies report experiencing phage contamination issues.
• Current methods lack effective strategies for preventing bacteriophage infections.

Purpose of the Study:

• To develop a novel nanoparticle-based technology for irreversible bacteriophage deactivation.
• To ensure the safety of the proposed method for industrial bacteria.
• To provide unsupervised protection for bacterial processes against phage threats.

Main Methods:

• Gold nanoparticles were synthesized and coated with a mixture of 11-mercapto 1-undecanesulfonic acid (MUS) and 1-octanethiol (OT) ligands.
• The efficacy of the nanoparticles in deactivating specific bacteriophages (T1, T4, T7) was tested.
• Nanoparticle toxicity to *Escherichia coli* and effectiveness under bioreactor-simulating conditions were evaluated.

Main Results:

• The MUS/OT-coated gold nanoparticles effectively deactivated various *Escherichia coli*-selective phages.
• Nanoparticles reduced phage titers by up to 2 and 5 logs within 6 and 24 hours at 50 °C, respectively.
• The combination of charged and hydrophobic ligands was crucial for achieving high inhibitory concentration (EC50 ≤ 1 μg mL⁻¹).

Conclusions:

• The developed nanoparticle technology offers an effective and safe solution for bacteriophage control in industrial bioreactors.
• The nanoparticles are non-toxic to *Escherichia coli* and function effectively under simulated bioreactor conditions.
• This innovation enables unsupervised protection against bacteriophage infections, addressing a critical challenge in biotechnology.