One step antimicrobial coatings for medical device applications based on low fouling polymers containing selenium nanoparticles

Abstract

All indwelling and implantable medical devices are associated with a risk of infection, and antimicrobial technologies that can provide effective protection against pathogen colonization and biofilm formation over the lifetime of these devices are urgently required. Here, strategies that combine multiple layers of defense have emerged as particularly promising. We have combined a copolymer coating based on 2-hydroxypropyl acrylamide and N-benzophenone acrylamide with novel, optimally sized antimicrobial selenium nanoparticles (Se NPs). The photoreactive polymer allowed the crosslinking and covalent anchoring of the coating in a single step, and the exceptionally low attachment of bacteria was demonstrated. Our results also demonstrated that the incorporation of the antimicrobial Se NPs provides the coating with an additional bactericidal functionality towards the Gram-positive bacteria S. aureus and E. faecalis, which are widely recognized as the most prevalent pathogens linked to medical device-associated infections and more broadly nosocomial infections. The multiple layers of defense provided effective inhibition of the growth of both bacteria strains in areas where the coating had been removed, as well as in the supernatant. Moreover, our results demonstrate the feasibility to modulate the release of Se NPs from the coating by tailoring coating parameters such as the nanoparticle to polymer ratio. Our cytotoxicity study further confirmed the superior biocompatibility of Se NPs compared to the well-established silver nanoparticles over a broad concentration range. Our multifunctional coating approach is expected to be translated into medical device applications due to its ease of manufacture and effective antimicrobial protection.