Identification of Structural Attributes Contributing to the Potency and Selectivity of Antimicrobial Polyionenes: Amides Are Better Than Esters.

Polyionenes are a unique class of materials in which the charges reside along the polymer backbone and have emerged as an important class of antimicrobials. In this study, we have synthesized polyionenes based on quaternary ammonium salts consisting of amides or esters or amide/ester combinations. These materials have a broad spectrum of antimicrobial activity against various types of pathogenic microbes and exhibit a low minimum inhibitor concentration. Importantly, polyionenes with amides outperformed esters in terms of their antimicrobial activity, selectivity, and killing kinetics. Our findings offer insights into the macromolecular design to access selective and potent antimicrobial agents.