title: The preparation of sugar polymer-coated nanocapsules by the layer-by-layer deposition on the liposome.
abstract: We intended to combine the liposomal preparation and the layer-by-layer deposition to prepare a nanosized capsule. Chitosan (CHI) was deposited to form the cationic polymeric layer onto a negatively charged liposomal surface and further deposition was carried out using anionic polymers dextran sulfate (DXS) or deoxyribonucleic acid (DNA). zeta-Potentials of nanocapsules changed between positive and negative charges at each deposition. FE-TEM revealed that the liposome remained a spherical shape even after the layer-by-layer (LbL) deposition. The capsule wall showed a dramatic increase in stability against the surfactant Triton X-100 compared to a bare liposome, and the stability was controllable by the adsorption amount of the polymer. These suggest that the polymer multilayer was generated on the liposome surface by the layer-by-layer depositions of polysaccharides. The three kinds of chemical substances with different charges, 1-hydroxy pyrene-3,6,8-trisulfonic acid (HPTS), alendronate, and glucose, were encapsulated into nanocapsules and the release was suppressed by the polymeric capsule wall irrespective of charges. The release from DNA-deposited nanocapsules (liponano-CHI-DNA) was clearly increased by raising temperature from 25 to 60 degrees C. This indicates that the temperature-dependent release was achieved by applying DNA denaturation as a temperature-dependent "switch", which influenced the permeability of the capsule wall.
authors.affiliation: Center for Chemical Biology, School of Fundamental Science and Technology, Graduate School of Science and Technology, Keio University, Kohoku-ku, Yokohama, 223-8522, Japan.
authors.forename: Yuuka
authors.initials: Y
authors.lastname: Fukui
authors.forename: Keiji
authors.initials: K
authors.lastname: Fujimoto
mesh_terms: D000327:Adsorption; D019386:Alendronate / Q000737:chemistry; D002241:Carbohydrates / Q000737:chemistry*; D002412:Cations; D003902:Detergents / Q000494:pharmacology; D005947:Glucose / Q000737:chemistry; D008081:Liposomes / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission / Q000379:methods; D053769:Nanocapsules; D053758:Nanoparticles / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods; D017830:Octoxynol / Q000494:pharmacology; D011108:Polymers / Q000737:chemistry*; D013501:Surface-Active Agents / Q000737:chemistry; D013696:Temperature
chemical_list: D002241:Carbohydrates; D002412:Cations; D003902:Detergents; D008081:Liposomes; D053769:Nanocapsules; D011108:Polymers; D013501:Surface-Active Agents; D017830:Octoxynol; D005947:Glucose; D019386:Alendronate