title: Remotely controlled diffusion from magnetic liposome microgels.
abstract: The reversible, temperature-dependent change in the permeability of a phospholipid bilayer has been used for controlling the diffusion rate of encapsulated molecular payload from liposomes. Liposomes were preloaded with a fluorescent dye and immobilized in calcium alginate hydrogel microparticles that also contained iron oxide nanoparticles. The composite microparticles were produced by a drop-on-demand inkjet method. The ability of iron oxide nanoparticles to locally dissipate heat upon exposure to a radio-frequency (RF) alternating magnetic field was used to control the local temperature and therefore diffusion from the liposomes in a contactless way using an RF coil. Several different release patterns were realized, including repeated on-demand release. The internal structure of the composite alginate-liposome-magnetite microparticles was investigated, and the influence of microparticle concentration on the heating rate was determined. In order to achieve a temperature rise required for the liposome membrane melting, the concentration of alginate beads should be at least 25% of their maximum packing density for the nanoparticle concentration and specific absorption rate used.
authors: Department of Chemical Engineering, Institute of Chemical Technology, Prague, Czech Republic.
authors: Jaroslav
authors: J
authors: Hanuš
authors: Martin
authors: M
authors: Ullrich
authors: Jiří
authors: J
authors: Dohnal
authors: Mandeep
authors: M
authors: Singh
authors: František
authors: F
authors: Stěpánek
mesh_terms: D000464:Alginates / Q000737:chemistry*; D004058:Diffusion; D005290:Ferric Compounds / Q000737:chemistry; D005456:Fluorescent Dyes / Q000737:chemistry; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000737:chemistry*; D008081:Liposomes / Q000737:chemistry*; D060526:Magnetic Fields; D053758:Nanoparticles / Q000737:chemistry; D010316:Particle Size; D013499:Surface Properties; D013696:Temperature
chemical_list: D000464:Alginates; D005290:Ferric Compounds; D005456:Fluorescent Dyes; D006603:Hexuronic Acids; D008081:Liposomes; C000499:ferric oxide; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D020723:Glucuronic Acid