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Poly(oxanorbornene)s bearing TPP and PEGylated ZnPc with varying compositions have been synthesized. Thus, highest reported singlet oxygen generation for a Pc derivative in water (ΦΔ = 0.93) and excellent biological activity have been accomplished.

In this study, phosphonium salt-bearing polynorbornenes were synthesized using five different aromatic side chains (triphenylphosphonium, trifluorophenyl phosphonium, trichlorophenyl phosphonium, tri(p-tolyl)phosphonium, and cyclohexyldiphenyl phosphonium) via ring-opening metathesis polymerization (ROMP). The biological activities of these polymers were determined by their minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against Escherichia coli and Staphylococcus aureus, and additionally, cytotoxicity studies on red blood cells were performed to report on their hemolytic activities (HC50). All of the synthesized polymers were found to be more active toward S. aureus than E. coli, and among them, tri(p-tolyl)phosphonium-and cyclohexyldiphenyl phosphonium-bearing homopolymers were found to be the most active against S. aureus (MIC: 2 mu g mL(-1)) under the Mueller Hinton Broth (MHB) medium; however, the polymers were also found to be hemolytic (HC50

Amphiphilic poly(oxanorbornene)s are promising synthetic polymers that mimic the structural properties and antimicrobial functions of naturally occurring antimicrobial peptides. Here, poly(oxanorbornene)s bearing pendant zinc(II) phthalocyanine and triphenyl(ethyl) phosphonium functionalities are synthesized by ring-opening metathesis polymerization (ROMP). Fluorescence, singlet oxygen and triplet quantum yields of polymers are measured in dimethyl sulfoxide and aqueous medium. The singlet oxygen quantum yields of copolymers with the highest triphenyl and triethyl phosphonium content are found to be 0.29 and 0.41, respectively. Then, antimicrobial activities of polymers against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) are investigated under both dark and light conditions. Synergistic effect of zinc(II) phthalocyanine and phosphonium-containing poly(oxanorbornene) is observed that the conjugate possessing the most triphenyl phosphonium side chains has the highest activity under light against both gram-positive and gram-negative bacterial strains after 80 min irradiation, reducing the survival of E. coli or S. aureus by 99.9999%. Hemolytic concentrations of the copolymers are found between 8 and 512 mu g mL(-1). Scanning electron microscopy (SEM) proves that the bacteria membrane deforms after contacting with the biocidal polymer.

Cationic ROMP-polymers bearing ammonium or phosphonium groups were photo-grafted onto a PDMS surface via the thiol-ene click reaction, in the presence of benzophenone. The PDMS surface was first thiolated using pentaerythritol tetrakis (3-mercaptopropionate) (PTTMP) under UV, in the presence of benzophenone. The obtained cationic surfaces exhibited charge densities above 1014 charge/cm2 and a higher degree of hydrophilicity compared to non-grafted surfaces. The live and dead tests performed by fluorescence microscopy revealed an effective contact bactericidal effect of these surfaces against Escherichia coli and Staphylococcus epidermidis.

The introduction of cationic groups onto the surface of gold nanoparticles (GNPs) is a valuable synthetic technique with many applications. This study reports the synthesis of the functionalization of GNPs with phosphonium groups presented in the ring opening metathesis (ROMP)-type polymer backbone. The formation of nanoparticles was revealed with UV-spectroscopy and Transmission Electron Microscopy (TEM). The presence of polyphosphonium ligand on the surface of the GNPs was confirmed by XPS and 31P NMR spectroscopy. Higher molecular weight polymer-GNPs exhibited better stability in the ambient conditions than the phosphonium polymers which possessed lower molecular weights. Phosphonium-based polymers can act, simultaneously, as reducing and stabilizing agents for the gold nanoparticles.

Bacterial surface contamination is considered as one of the main causes of secondary infection. Herein, cationic polymers containing alkyl or aromatic quaternary phosphonium groups were synthesized via ring opening metathesis polymerization (ROMP) and successfully deposited onto a glass surface via a spin coating or dip coating process in an effort towards preventing biofilm formation. The polymer bearing phenyl units with a molecular weight of 3000 g mol –1 (G_Phenyl_3k) exhibited the highest bactericidal efficiency against an E. coli contaminated solid surface with a bacteria killing efficiency of 80%. However, increasing the molecular weight of the polymer (10,000 g mol –1 ) caused a dramatic decrease in the bactericidal activity (10%). Polymers bearing alkyl group also exhibited lower biocidal activity on the solid surface, which was similar to that observed in solution. The bactericidal effect of the active surfaces against E. coli were confirmed using a live and dead fluorescent assay. The accessible surface positive charge density of the as-prepared polymer-coated surfaces was calculated using a staining with fluorescein sodium salt and varied from 3.5 × 10 14 to 1.9 × 10 15 charge cm –2 . The dispersive and the polar components of the surface energy as well as polarity of the coated surfaces were also evaluated using contact angle measurements. The surface polarity (%), cationic charge density and threshold concentration were found to influence the biocidal activity observed on the polymer-coated solid surfaces.

In this study, amphiphilic polyoxanorbornene with different alkyl and aromatic phosphonium side chains was synthesized. The biological activities of these polymers were determined by the minimal inhibitory concentration (MIC) against E. coli, S. aureus, M. tuberculosis and the yeast C. albicans, and cytotoxicity studies on red blood cells were performed. A series of polymers with different alkyl and aromatic substituents (methyl, ethyl, tripropyl, tert-butyl, phenyl, and tris 4-methoxyphenyl) and two types different molecular weight, 3000 g mol(-1) and 10 000 g mol(-1), were prepared. It was observed that the biological activity of the polymers with aromatic group substituents had an MIC of 16, 8, 64 and 128 mu g mL(-1) against E. coli, S. aureus, M. tuberculosis and C. albicans, respectively, while those with nonaromatic carbons had a higher MIC compared to those with aromatic carbons. The aromaticity of the repeat unit had impressive effects on hemolytic activities as well. Zeta potential measurements of E. coli incubated with active and inactive polymer concentration revealed a relationship between the MIC and membrane surface charge density. Polymers bearing aromatic groups killed the bacteria with widespread damage after the polymers, holding the threshold concentration, were added to the bacteria., Scientific and Technological Research Council of Turkey (TÜBİTAK); COST Action CM1302 SIPs