title: Self-assembled nanoparticles of modified-chitosan conjugates for the sustained release of DL-α-tocopherol.
abstract: Synthetic O6-succinylated chitosan and commercial glycol chitosan were covalently linked to dl-α-tocopheryl monoesters for controlled release of vitamin E. These conjugates formed self-assembled nanoparticles in aqueous solution with 254-496 nm mean diameters and dl-α-tocopherol contents between 27 and 39% (w/w). The particles appeared as 40-75 nm almost spherical nanoparticles when studied by scanning and transmission electron microscopy upon drying. Drug linking to chitosan matrix was confirmed by FTIR spectroscopy and proton NMR. Conjugates were also characterized by differential scanning calorimetry and wide-angle X-ray diffraction. In vitro tocopherol release studies performed in water at acid pH indicated a drug release dependence on drug content, hydrated particle sizes and employed chitosan derivative. Almost constant release rates were observed the first 7h. The obtained nanoparticles exhibited radical scavenging activity in DPPH essay. The potential of these nanoparticles was also demonstrated by the enhancement of HMVEC cell proliferation.
authors.affiliation: Center of Natural Products, Faculty of Chemistry, University of Havana, Havana, Cuba. javierp@fq.uh.cu
authors.forename: Javier Pérez
authors.initials: JP
authors.lastname: Quiñones
authors.forename: Kurt Vesterager
authors.initials: KV
authors.lastname: Gothelf
authors.forename: Jørgen
authors.initials: J
authors.lastname: Kjems
authors.forename: Chuanxu
authors.initials: C
authors.lastname: Yang
authors.forename: Angeles María Heras
authors.initials: AM
authors.lastname: Caballero
authors.forename: Claudia
authors.initials: C
authors.lastname: Schmidt
authors.forename: Carlos Peniche
authors.initials: CP
authors.lastname: Covas
mesh_terms: D048271:Chitosan / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000138:chemical synthesis / Q000737:chemistry*; D004337:Drug Carriers / Q000008:administration & dosage / Q000737:chemistry; D006367:HeLa Cells / Q000187:drug effects; D006801:Humans; D061986:MCF-7 Cells / Q000187:drug effects; D009682:Magnetic Resonance Spectroscopy; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000008:administration & dosage / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D014867:Water / Q000737:chemistry; D024502:alpha-Tocopherol / Q000008:administration & dosage / Q000737:chemistry
chemical_list: D004337:Drug Carriers; C118638:glycol-chitosan; D014867:Water; D048271:Chitosan; D024502:alpha-Tocopherol