Preparation of bactericidal surfaces with high quaternary ammonium content through photo-initiated polymerization of N-[2-(acryloyloxy)ethyl]-N,N-dimethyl-N-butylammonium iodide from native and thiolated PDMS surfaces

N-[2-(acryloyloxy)ethyl]-N,N-dimethyl-N-butylammonium iodide was successfully photo-polymerized from native and thiolated PDMS surface, in the presence of benzophenone. The directly and indirectly grafted surfaces exhibited quaternary ammonium densities of about 1015 and 1017 N+.cm−2, respectively, and very high hydrophilicity compared to non-grafted surfaces. The live and dead tests performed by fluorescence microscopy revealed an effective contact bactericidal effect of this surface against Escherichia coli and Staphylococcus epidermidis. [Display omitted] •Preparation of highly quaternary ammonium functionalized PDMS surfaces by two ‘grafting from’ processes.•Photopolymerization of N-[2-(acryloyloxy)ethyl]-N,N-dimethyl-N-butylammonium iodide from native/thiolated PDMS surfaces.•The direct grafting led to surface charge densities around 1015 charge/cm2.•The indirect grfating led to surface charge densities around 1017 charge/cm2.•The obtained surfaces effectively kill surface bacteria.