title: Release of small hydrophilic molecules from polyelectrolyte capsules: effect of the wall thickness.
abstract: Polymer nanocapsules assembled on cationic liposomes have been built through the layer-by-layer (LbL) technique. Chitosan and alginate, two biocompatible polyelectrolytes, were used to cover the template, where the Rhodamine B was previously loaded. The multishell formed with the alternate deposition of the polyelectrolytes, according to the principles of the LbL assembly, was supposed to change the permeability of the capsule wall. The thickness of the multishell was seen increasing with the number of layers deposited through the observations with the Transmission Electron Microscope. The permeability of the capsules was studied through Rhodamine B release assays. Nanocapsules with seven layers of polyelectrolytes released the dye slowly compared to the capsules with three or five layers. The Ritger-Peppas model was applied to investigate the release mechanisms and a non-Fickian transport behavior was detected regardless of the number of layers. Values of diffusion coefficients of Rhodamine B through the capsule wall were also calculated.
authors.affiliation: Dipartimento di Agricoltura, Ambiente Alimenti (DIAAA) and CSGI, Università degli Studi del Molise, Via De Sanctis, I-86100 Campobasso, Italy. Electronic address: francesca.cuomo@unimol.it.
authors.forename: Francesca
authors.initials: F
authors.lastname: Cuomo
authors.affiliation: Dipartimento di Agricoltura, Ambiente Alimenti (DIAAA) and CSGI, Università degli Studi del Molise, Via De Sanctis, I-86100 Campobasso, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Lopez
authors.affiliation: Dipartimento di Scienze Biomediche, Università di Cagliari, Cittadella Universitaria, S.S. 554 bivio Sestu, 09042 Monserrato, CA, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Piludu
authors.affiliation: Chemistry Department, Coimbra University, 3004-535 Coimbra, Portugal; School of Materials Science & Engineering, Nanyang Technological University, Singapore.
authors.forename: Maria G
authors.initials: MG
authors.lastname: Miguel
authors.affiliation: Physical Chemistry, Lund University, P.O. Box 124, 22100 Lund, Sweden; School of Materials Science & Engineering, Nanyang Technological University, Singapore; FSCN, Fibre Science and Communication Network, MidSweden University, Sundsvall, Sweden.
authors.forename: Bjorn
authors.initials: B
authors.lastname: Lindman
authors.affiliation: Dipartimento di Agricoltura, Ambiente Alimenti (DIAAA) and CSGI, Università degli Studi del Molise, Via De Sanctis, I-86100 Campobasso, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Ceglie
mesh_terms: D000464:Alginates / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D008081:Liposomes; D046529:Microscopy, Electron, Transmission; D053769:Nanocapsules / Q000737:chemistry* / Q000648:ultrastructure; D011108:Polymers / Q000737:chemistry*; D012235:Rhodamines / Q000737:chemistry*
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D008081:Liposomes; D053769:Nanocapsules; D011108:Polymers; D012235:Rhodamines; D020723:Glucuronic Acid; D048271:Chitosan; C029773:rhodamine B
keywords: Layer by layer; Molecule release; Multishell thickness; Polyelectrolyte nanocapsules