Self-assembled cationic peptide nanoparticles as an efficient antimicrobial agent

Antimicrobial cationic peptides are of interest because they can combat multi-drug-resistant microbes. Most peptides form α-helices or β-sheet-like structures that can insert into and subsequently disintegrate negatively charged bacterial cell surfaces. Here, we show that a novel class of core–shell nanoparticles formed by self-assembly of an amphiphilic peptide have strong antimicrobial properties against a range of bacteria, yeasts and fungi. The nanoparticles show a high therapeutic index against Staphylococcus aureus infection in mice and are more potent than their unassembled peptide counterparts. Using Staphylococcus aureus -infected meningitis rabbits, we show that the nanoparticles can cross the blood–brain barrier and suppress bacterial growth in infected brains. Taken together, these nanoparticles are promising antimicrobial agents that can be used to treat brain infections and other infectious diseases. A class of core–shell nanoparticles self-assembled from amphiphilic peptides can kill a range of bacteria, yeast and fungus. They are more potent than their unassembled peptide counterparts and can suppress bacterial growth in the brains of rabbits infected with meningitis. These particles, which carry a high number of positive charges, are promising antimicrobial agents.