Nanoporous multilayer films for controlled antigen protein release

We have studied the preparation and characterization of nanoporous thin films fabricated from a layer by layer assembly of branched poly(ethylene imine), gold nanoparticles (gold NPs) and hyaluronic acid. Gold NPs embedded in the multilayer thin film structure were easily dissolved using an aqueous cyanide solution, generating the nanoporous film. This allows for the direct and precise comparison of the porosity of the polymer based multilayer thin films in both the presence and the absence of gold NPs. Additionally, the layer by layer (LbL) assembly method has advantages in that it increases the possibilities for mass production of multilayer films, and allows the precise control of film structures prepared on large substrates. Therefore, this method offers a new route to allow the introduction of nanoporosity into multilayer thin films, allowing the development of more complex functional multicomponent nanoporous structures for protein delivery. Furthermore, these novel materials could be used in biomedical applications.