Preparation of Biodegradable Hollow Nanocapsules by Silica Template Method

Biodegradable hollow nanocapsules were successfully prepared by a combination of layer-by-layer assembly and the silica template method. Ultrathin polymer films were constructed on the surface of the silica nanoparticles by layer-by-layer assembly of oppositely charged biodegradable polyelectrolytes, chitosan and dextran sulfate. The silica templates were easily removed from the ultrathin polymer film-coated nanoparticles by treatment with hydrofluoric acid solution to create hollow nanocapsules. The hollow shape of these biodegradable nanocapsules was confirmed by SEM observation.