The antimicrobial agent cetyltrimethylammonium bromide (CTAB) has been placed in the cationic layer of LbL assemblies, with polyacrylic acid (PAA) as the anionic layer (Langmuir 2009). When the films are exposed to a humid environment, these agents diffuse out of the film, stopping bacteria in neighboring regions.
As more layers are deposited, antimicrobial efficacy is increased because CTAB is able to diffuse throughout the film. These transparent films are capable of sterilizing a surface and this technology could also be the basis for film-based drug delivery (e.g. drug-eluting patch).
