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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.