Objectives: The aim of this study is to develop a new type of surface protection using the polyelectrolyte multilayer film technique allowing the incorporation of antimicrobial peptides, derived from naturally occuring peptides of the innate immunity,in order to inhibit the pathogen growth at the interface.
Methods: Characterization of the peptide (defensin) insertion in the film is studied with optical wave-mode light spectroscopy (OWLS), quartz crystal microbalance (QCM-D) and streaming potential measurements. Antimicrobial assays are performed on two bacterial strains (E. coli ; M. luteus), and one filamentous fungus (N. crassa). Stability of the film in the presence of saliva and towards brushing is observed, in vitro, with fluorescent microscopy.
Results: The film presents a good stability in the salivary environment. Even a mechanical action such as a brushing seems able to remove only a small part of the film. The insertion of the peptides is confirmed by OWLS, QCM-D and streaming potential measurements. The pathogen growth is inhibited by more than 80% when antimicrobial peptides are inserted in the film.
Conclusion: The use of antimicrobial peptides may overcome the problems of resistances with the antibiotics and antifungics currently used. Their incorporation into a polyelectrolyte multilayer film confers a local protection, at the level of the implanted site, precisely at the interface of the material and the surrounding biological tissues.