Synthesis and characterization of phosphonium-containing romp based polymers and investigation of their antibacterial activity

Bacteria infection is a global problem. Especially in recent years, growing resistance against to antibiotic, result in spread of infection diseases and increasing in mortality. The surface modification of implant materials (such as catheters) and developing new generation antibiotics play an important role during the fight against to bacteria. However, there are two main strategy present. First one is synthesis of host defense peptides, the second one is the synthetic mimic of host defense peptides. In this thesis, one of the controlled polymerization techniques ROMP (ring opening metathesis polymerization) is used for phosphonium based homopolymers. The effect of hydrophobicity on the antimicrobial activity was investigated by using different alkyl and aromatic groups (phenyl, methoxyphenyl, methyl, ethyl, propyl, tert-butyl) bearing at phosphonium salts. Antimicrobial activity of the polymers was investigated against to E. coli, S. aureus and C. albicans. Cytotoxicity of the polymers was evaluated by hemolytic concentration (HC50). In this study, solution phase activity of the polymers have been analyzed and surface activity (on glass) was also investigated by cationic polymer coated glass surface as well. Charge density, contact angle studies were applied on the polymer coated glass surface to speculate the hydrophobic/hydrophilic properties against to antimicrobial activity. Fluorescence microscopy is used to analyze interaction between the amphiphilic polymer and bacteria cell membrane and result in death of bacteria. Structure-activity relationship was also investigated by zeta potential studies.