title: Loading and protection of hydrophilic molecules into liposome-templated polyelectrolyte nanocapsules.
abstract: Compartmentalized systems produced via the layer-by-layer (LbL) self-assembly method have been produced by alternatively depositing alginate and chitosan layers onto cores of liposomes. The combination of dynamic light scattering (DLS), ζ potential, and transmission electron microscopy (TEM) techniques provides detailed information on the stability, dimensions, charge, and wall thickness of these polyelectrolyte globules. TEM microphotographs demonstrate the presence of nanocapsules with an average diameter of below 300 nm and with a polyelectrolyte wall thickness of about 20 nm. The possibility of encapsulating and releasing molecules from this type of nanocapsule was demonstrated by loading FITC-dextrans of different molecular weights in the liposome system. The release of the loaded molecules from the nanocapsule was demonstrated after liposome core dissolution. Even at low molecular weight (20 kDa), the nanocapsules appear to be appropriate for prolonged molecule compartmentalization and protection. By means of the Ritger-Peppas model, non-Fickian transport behavior was detected for the diffusion of dextran through the polyelectrolyte wall. Values of the diffusion coefficient were calculated and yield useful information regarding chitosan/alginate hollow nanocapsules as drug-delivery systems. The influence of the pH on the release properties was also considered. The results indicate that vesicle-templated hollow polyelectrolyte nanocapsules show great potential as novel controllable drug-delivery devices for biomedical and biotechnological applications.
authors.affiliation: Dipartimento di Agricoltura, Ambiente Alimenti (DIAAA) and CSGI, Università degli Studi del Molise ,Via De Sanctis, I-86100 Campobasso, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Cuomo
authors.forename: Andrea
authors.initials: A
authors.lastname: Ceglie
authors.forename: Marco
authors.initials: M
authors.lastname: Piludu
authors.forename: Maria G
authors.initials: MG
authors.lastname: Miguel
authors.forename: Björn
authors.initials: B
authors.lastname: Lindman
authors.forename: Francesco
authors.initials: F
authors.lastname: Lopez
mesh_terms: D000464:Alginates / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D055032:Electron Microscope Tomography; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008081:Liposomes / Q000737:chemistry* / Q000648:ultrastructure; D053769:Nanocapsules / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D008081:Liposomes; D053769:Nanocapsules; D020723:Glucuronic Acid; D048271:Chitosan