Aggregation of methacrylate-based ternary biomimetic antimicrobial polymers in solution

Area of Science:

• Polymer Science
• Biomaterials Science
• Computational Chemistry

Background:

• Biomimetic antimicrobial (AM) polymers are designed to mimic natural antimicrobial peptides.
• Understanding aggregate formation in solution is crucial for AM agent efficacy and membrane interaction.
• Previous studies focused on binary polymers, lacking insight into ternary systems.

Purpose of the Study:

• To investigate the morphological characteristics of aggregates formed by ternary AM methacrylate polymers.
• To compare these morphologies with those of binary AM methacrylate polymers.
• To elucidate the role of polar groups and sequence on aggregate formation and polymer behavior.

Main Methods:

• Detailed atomistic simulations were employed to explore aggregate structures.
• Comparison between ternary (hydrophobic, cationic, polar) and binary (hydrophobic, cationic) polymers.
• Analysis of random and block sequences of functional groups along the polymer backbone.
• Interaction energy calculations were performed.

Main Results:

• Binary polymers form robust aggregates, while ternary polymers, especially random sequences, form weaker, loose-packed aggregates.
• Inclusion of polar groups reduces local hydrophobic concentration, increasing polymer solubility.
• Polar groups also contribute to aggregation via electrostatic interactions, albeit weaker than hydrophobic ones.

Conclusions:

• Polar groups play a tuneable role in AM polymer aggregation, influencing solution behavior.
• The findings provide insights into the self-assembly of biomimetic AM agents.
• Understanding these interactions is key to controlling their partitioning into bacterial and mammalian membranes.