title: High transfection efficiency promoted by tailor-made cationic tri-block copolymer-based nanoparticles.
abstract: Cationic polymer-based vectors have been considered a promising strategy in gene therapy area due to their inherent ability to condense genetic material and successfully transfect cells. However, they usually exhibit high cytotoxicity. In this work, it is proposed the use of a tailor-made gene carrier based on a tri-block copolymer of poly[2-(dimethylamino)ethyl methacrylate] and poly(β-amino ester) (PDMAEMA-b-PβAE-b-PDMAEMA), the influence of the PβAE length being assessed. For this purpose, three different block copolymers were prepared varying the molecular weight of this segment. The obtained materials were characterized by NMR and SEC analyzes. Different polyplexes formulations were prepared and evaluated in terms of physicochemical characterization (ethidium bromide intercalation assay, agarose gel electrophoresis assay, dynamic light scattering, zeta potential analyzes and atomic force microscopy) and biological activity (cytotoxicity, and luciferase and green fluorescent protein expression in Hela and COS-7 cell lines). Among the developed nanosystems, the best polyplex formulation revealed between 40- and 60-fold higher transgene expression, in HeLa and COS-7 cell lines, and much lower cytotoxicity than that observed with branched PEI and TurboFect™. Moreover, these nanosystems present suitable physicochemical properties for gene delivery namely reduced mean diameter and high DNA protection. The results reported here show the enormous potential of this block copolymer as gene carrier.
  
  
  
  Syntheses of PDMAEMA-b-PβAE-b-PDMAEMA block copolymers for an extremely effective non-viral vector. The block copolymer PDMAEMA3000-b-PβAE12000-b-PDMAEMA3000-based polyplexes at 100/1N/P ratio exhibits between 40- and 60-fold higher transgene expression in HeLa and COS-7 cell lines than commonly used polymeric non-viral vectors, namely branched PEI (known as the gold standard) and TurboFect™ (commercial available).
authors.affiliation: CEMUC, Department of Chemical Engineering, University of Coimbra, 3030-790 Coimbra, Portugal.
authors.forename: Rosemeyre A
authors.initials: RA
authors.lastname: Cordeiro
authors.affiliation: CNC, Center for Neuroscience and Cell Biology, University of Coimbra, Rua Larga, 3004-504 Coimbra, Portugal.
authors.forename: Daniela
authors.initials: D
authors.lastname: Santo
authors.affiliation: CNC, Center for Neuroscience and Cell Biology, University of Coimbra, Rua Larga, 3004-504 Coimbra, Portugal.
authors.forename: Dina
authors.initials: D
authors.lastname: Farinha
authors.affiliation: CEMUC, Department of Chemical Engineering, University of Coimbra, 3030-790 Coimbra, Portugal.
authors.forename: Arménio
authors.initials: A
authors.lastname: Serra
authors.affiliation: CNC, Center for Neuroscience and Cell Biology, University of Coimbra, Rua Larga, 3004-504 Coimbra, Portugal. Electronic address: henrique@cnc.uc.pt.
authors.forename: Henrique
authors.initials: H
authors.lastname: Faneca
authors.affiliation: CEMUC, Department of Chemical Engineering, University of Coimbra, 3030-790 Coimbra, Portugal. Electronic address: jcoelho@eq.uc.pt.
authors.forename: Jorge F J
authors.initials: JFJ
authors.lastname: Coelho
mesh_terms: D000818:Animals; D019556:COS Cells; D002412:Cations; D002470:Cell Survival; D002522:Chlorocebus aethiops; D004247:DNA / Q000378:metabolism; D004587:Electrophoresis, Agar Gel; D004705:Endocytosis; D004996:Ethidium / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D008689:Methacrylates / Q000737:chemistry; D008856:Microscopy, Fluorescence; D053758:Nanoparticles / Q000737:chemistry*; D009757:Nylons / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D014162:Transfection / Q000379:methods*
chemical_list: D002412:Cations; D008689:Methacrylates; D009757:Nylons; D011108:Polymers; C407037:poly(2-(dimethylamino)ethyl methacrylate); C507253:poly(beta-amino ester); D004247:DNA; D004996:Ethidium
keywords: Block copolymer; Click chemistry; Gene delivery; Poly(beta-amino ester); Poly[2-(dimethylamino)ethyl methacrylate]