ANTIMICROBIAL ACTIVITY AND MECHANISTIC STUDY FOR THE POLY(PHENYLENE ETHYNYLENE) (PPE)-BASED CATIONIC CONJUGATED POLYELECTROLYTES AND OLIGO-PHENYLENE ETHYNYLENES

My dissertation work focuses on recent progress made in elucidating the intermolecular interactions between a novel class of synthetic phenylene ethynylene (PPE)-based conjugated polyelectrolyte polymers (CPEs) and oligomers (OPEs) and multiscale cellular targets that give rise to their remarkable broad spectrum biocidal activity. We studied the interactions and self-assembly behaviors of the CPEs and OPEs with a set of vital biomolecules, including lipids, proteins and nucleic acids, that reveal the potential pathways by which the synthetic biocidal agents could exert toxicity. Then, we explored the antimicrobial effects and mechanisms of the CPEs and OPEs on multiple clinically relevant pathogens, with an emphasis on the morphological damages induced by the biocidal compounds towards the pathogens. The discussion about the cytotoxicity of these materials against mammalian cells and human tissues to can help us to explore the potential applications of the CPEs and OPEs as antiseptics. We also pose some unanswered questions about their antimicrobial mechanisms, which provide directions for the future study