(486e) Vapor Phase Photografting of Antimicrobial Polymer Coatings

An all-dry vapor phase photografting process is employed to covalently attach antimicrobial polymer coatings to polymeric substrates, including both spun-cast PMMA layers and nylon fabric. Antimicrobial fabrics are of interest in military applications, such as biowarfare protection, self-decontaminating fabrics, undergarments for long term use on deployment, as well as civilian uses such as clothing for athletes and hikers, and textiles in hospital environments, including bedding, draping, and scrubs. Antimicrobial coatings are also of interest for use on medical devices. Microbial colonization of medical devices is associated with significant expense and mortality. A permanent, durable non-leaching antimicrobial surface is important for both of these applications. A fabric coating must survive many wash cycles, and a medical device coating must not detach in the body. Existing strategies for imparting antimicrobial properties to surfaces commonly employ an antimicrobial agent, such as silver ions or antibiotic drugs, which leaches out from the bulk material. However, the time of effectiveness will be limited as the agent will eventually be exhausted. Additionally, the use of antibiotic drugs with medical devices has potential to promote drug resistant microbes, whereas the class of antimicrobial polymers under examination here has not been shown to do so. In this work, the type-II photoinitiator benzophenone is used in conjunction with methacrylate- or styrene- based monomer containing a tertiary amino group with pKa > 9. The amino group is protonated to a cationic state at physiological conditions. The coatings were tested according to ASTM E2149-01, and demonstrated good antimicrobial activity against e. coli, with a 99.999% reduction (5 log) in viable bacteria. In addition, the coatings show no zone of inhibition against e. coli, indicating the active polymer is not leaching from the surface. Finally, the active surface is maintained through various durability testing.