Biomaterials,
which release active compounds after implantation, are an essential
tool for targeted regenerative medicine. In this study, thin multilayer
films loaded with lipid/DNA complexes (lipoplexes) were designed as
surface coatings for in situ transfection applicable in tissue engineering
and regenerative medicine. The film production and embedding of lipoplexes
were based on the layer-by-layer (LbL) deposition technique. Hyaluronic
acid (HA) and chitosan (CHI) were used as the polyelectrolyte components.
The embedded plasmid DNA was complexed using a new designed cationic
lipid formulation, namely, OH4/DOPE 1/1, the advantageous characteristics
of which have been proven already. Three different methods were tested
regarding its efficiency of lipid and DNA deposition. Therefore, several
surface specific analytics were used to characterize the LbL formation,
the lipid DNA embedding, and the surface characteristics of the multilayer
films, such as fluorescence microscopy, surface plasmon resonance
spectroscopy, ellipsometry, zeta potential measurements, atomic force
microscopy, and scanning electron microscopy. Interaction studies
were conducted for optimized lipoplex-loaded polyelectrolyte multilayers
(PEMs) that showed an efficient attachment of C2C12 cells on the surface.
Furthermore, no acute toxic effects were found in cell culture studies,
demonstrating biocompatibility. Cell culture experiments with C2C12
cells, a cell line which is hard to transfect, demonstrated efficient
transfection of the reporter gene encoding for green fluorescent protein.
In vivo experiments using the chicken embryo chorion allantois membrane
animal replacement model showed efficient gene-transferring rates
in living complex tissues, although the DNA-loaded films were stored
over 6 days under wet and dried conditions. Based on these findings,
it can be concluded that OH4/DOPE 1/1 lipoplex-loaded PEMs composed
of HA and CHI can be an efficient tool for in situ transfection in
regenerative medicine.