Antimicrobial polymer coatings on surfaces: preparation and activity

Antimicrobial polymers have been intensively studied as a promising strategy to suppress the growth of microbes and mitigate the transmission of pathogens owing to their distinctive properties, such as high molecular weights, tunable structures, functionality, and polyvalency. Unlike the monomers, the repetitive structure and polyvalency of polymers enable robust interactions with the target surfaces to provide synergetic functionality. Antimicrobial polymers have a great variety of adjustable chain lengths and surface chemistry. Furthermore, their backbones can be functionalized with bioactive substituents to interact with cell membranes, lipids, and proteins. The surface coating methods and the resulting antimicrobial activities depend on polymer characteristics, such as the combination of monomers, synthetic methods, contact time, and substrates. This review focuses on representative antimicrobial polymers, including hydrophilic and ionic polymers, polysaccharides, and copolymers containing amine groups and quaternary ammonium cations (QACs). The surface application strategies and antimicrobial properties for each polymer type are also discussed to provide inspiration for the advanced design of antimicrobial polymers.Graphical abstractSchematic illustration of antifouling- or microbicidal polymers coated on solid surfaces.