Antimicrobial Activity of Copolymer Structures from Bio-Based Monomers

The urgent need for new antimicrobial compounds has led scientists to explore antimicrobial peptides (AMPs) and antimicrobial polymers as solutions for multidrug resistance. In this study, we synthesized copolymers with cationic and hydrophobic moieties by free-radical polymerization (FRP) using a chain transfer agent to control molecular weights. The potential of natural products as part of the hydrophobic moiety was evaluated, along with variations in their monomer content (13-25%) and the molecular weight (MW) of the copolymer (5000-20,000 g·mol^-1). Hydrophobicity was evaluated using the theoretical Log P_oct values and surface areas (SAs). Biological assays included antimicrobial activity against Escherichia coli and Staphylococcus aureus standard strains, hemolytic activity in red blood cells (RBC), and cytotoxicity tests against HEK293T cells. Keys findings indicate that copolymers with tropolone moieties, lower MWs, and an optimal balance between hydrophobic and cationic moieties show a promising basis for future generations of antimicrobials.