Cross-linked lyotropic liquid crystal particles functionalized with antimicrobial peptides

Area of Science:

• Biomaterials Science
• Drug Delivery
• Infectious Diseases

Background:

• Antimicrobial peptides (AMPs) offer a potential solution to antibiotic resistance.
• Poor serum stability limits the clinical application of AMPs.
• Developing stable AMP formulations is crucial for effective treatment.

Purpose of the Study:

• To enhance the serum stability of AMPs.
• To maintain the antibacterial efficacy of AMPs.
• To investigate AMP-loaded liquid crystal particles as a drug delivery system.

Main Methods:

• Covalent bonding of AMPs to cross-linked lyotropic liquid crystal particles (Pluronic F-127).
• Structural and chemical analysis using SAXS, FTIR, and Raman spectroscopy.
• Assessment of antibacterial activity against Staphylococcus aureus and serum stability.
• Cryogenic transmission electron microscopy for mode of action studies.

Main Results:

• Liquid crystal particles with covalently bonded AMPs demonstrated a 4-log reduction against Staphylococcus aureus.
• The liquid crystal structure was maintained with AMPs covalently attached.
• AMP-loaded particles exhibited significantly improved serum stability, retaining potency for 2 days compared to free AMPs.
• Cryo-TEM revealed particle-bacteria surface interactions.

Conclusions:

• Covalent bonding of AMPs to liquid crystal particles enhances their stability in serum while preserving antibacterial activity.
• This novel material represents a promising strategy for developing effective treatments against bacterial infections, including those caused by antibiotic-resistant strains.
• The findings provide valuable insights into the interaction of AMP-loaded particles with bacteria.