title: The influence of chitosan valence on the complexation and transfection of DNA: the weaker the DNA-chitosan binding the higher the transfection efficiency.
abstract: The DNA-chitosan polyplexes have attracted for some years now the attention of physical-chemists and biologists for their potential use in gene therapy, however, the correlation between the physicochemical properties of these polyplexes with their transfection efficiency remains still unclear. In a recent paper we demonstrated by means of DLS that the DNA-chitosan complexation is favored at acidic conditions considering that fewer amounts of chitosan were required to compact the DNA. As a second study, in the present work we analyze the influence of chitosan valence on the complexation and transfection of DNA. Three chitosans of different molecular weights (three different valences) are characterized as gene carriers at 25°C and pH 5 over a wide range of chitosan-Nitrogen to DNA-Phosphate molar ratios, N/P, by means of conductometry, electrophoretic mobility, isothermal titration calorimetry (ITC), transmission electron microscopy (TEM), atomic force microscopy (AFM), and β-galactosidase and luciferase expression assays.
authors.affiliation: Grupo de Nanomateriales y Materia Blanda, Departamento de Física de Materia Condensada, Facultad de Física, Universidad de Santiago de Compostela, E-15782 Santiago de Compostela, Spain. manuel_alatorre@yahoo.com.mx
authors.forename: Manuel
authors.initials: M
authors.lastname: Alatorre-Meda
authors.forename: Pablo
authors.initials: P
authors.lastname: Taboada
authors.forename: Florian
authors.initials: F
authors.lastname: Hartl
authors.forename: Tobias
authors.initials: T
authors.lastname: Wagner
authors.forename: Michael
authors.initials: M
authors.lastname: Freis
authors.forename: Julio R
authors.initials: JR
authors.lastname: Rodríguez
mesh_terms: D002151:Calorimetry; D048271:Chitosan / Q000737:chemistry* / Q000378:metabolism*; D003217:Conductometry; D004247:DNA / Q000378:metabolism* / Q000648:ultrastructure; D004553:Electric Conductivity; D004586:Electrophoresis; D006367:HeLa Cells; D006801:Humans; D018625:Microscopy, Atomic Force; D046529:Microscopy, Electron, Transmission; D013816:Thermodynamics; D014162:Transfection / Q000379:methods*
chemical_list: D004247:DNA; D048271:Chitosan