Contact-active antibacterial polyethylene foils via atmospheric air plasma induced polymerisation of quaternary ammonium salts

• Published in: Colloids and surfaces, B, Biointerfaces B, Biointerfaces, 2020-02, Vol.186, p.110679-110679, Article 110679
• Main Authors: Kliewer, Serge, Wicha, Sebastian G., Bröker, Astrid, Naundorf, Tim, Catmadim, Tugba, Oellingrath, Eva Katharina, Rohnke, Marcus, Streit, Wolfgang R., Vollstedt, Christel, Kipphardt, Helmut, Maison, Wolfgang
• Format: Article
• Language: English
• Subjects: Antifouling; Biocides; Contact-active materials; Quarternary ammonium salts
• ISSN: 0927-7765; 1873-4367
• DOI: 10.1016/j.colsurfb.2019.110679

[Display omitted] •Plasma activation followed by polymerization leads to antibacterial polyethylene.•Exceptional antibacterial activity against Gram-positive and Gram-negative microbes.•Materials provide long-term activity without release of biocides to surrounding media. Polyethylene (PE) foils were modified with potent contact-active antibacterial quaternary ammonium salts (QAS) by an atmospheric air plasma activation step, followed by graft-polymerisation of vinylbenzyltrimethylammonium chloride (VBTAC) monomers. The presented approach uses a cost efficient air plasma activation and subsequent radical polymerisation in highly concentrated aqueous monomer solutions to generate efficient antibacterial materials. The obtained contact-active poly-VBTAC modified PE foils feature a homogeneous and 300 nm thick polymer layer with a high charge density of approximately 1016 N+/cm2. The antibacterial properties were evaluated against Gram-negative (P. aeruginosa, E. coli) and Gram-positive (S. aureus, S. epidermidis) bacteria. The materials showed strong antibacterial activity by eradicating all the inoculated bacteria with bacterial challenges of 104 to 105 CFU/cm2 and good reductions even at maximum challenge (108 CFU/cm2). We have confirmed contact-activity by an agar diffusion assay. The obtained materials are therefore highly attractive for applications, for example, in packaging and are a contribution to an ecomic and green antimicrobial management without release of biocides to the environment.