title: Efficient Condensation of DNA into Environmentally Responsive Polyplexes Produced from Block Catiomers Carrying Amine or Diamine Groups.
abstract: The intracellular delivery of nucleic acids requires a vector system as they cannot diffuse across lipid membranes. Although polymeric transfecting agents have been extensively investigated, none of the proposed gene delivery vehicles fulfill all of the requirements needed for an effective therapy, namely, the ability to bind and compact DNA into polyplexes, stability in the serum environment, endosome-disrupting capacity, efficient intracellular DNA release, and low toxicity. The challenges are mainly attributed to conflicting properties such as stability vs efficient DNA release and toxicity vs efficient endosome-disrupting capacity. Accordingly, investigations aimed at safe and efficient therapies are still essential to achieving gene therapy clinical success. Taking into account the mentioned issues, herein we have evaluated the DNA condensation ability of poly(ethylene oxide)113-b-poly[2-(diisopropylamino)ethyl methacrylate]50 (PEO113-b-PDPA50), poly(ethylene oxide)113-b-poly[2-(diethylamino)ethyl methacrylate]50 (PEO113-b-PDEA50), poly[oligo(ethylene glycol)methyl ether methacrylate]70-b-poly[oligo(ethylene glycol)methyl ether methacrylate10-co-2-(diethylamino)ethyl methacrylate47-co-2-(diisopropylamino)ethyl methacrylate47] (POEGMA70-b-P(OEGMA10-co-DEA47-co-DPA47), and poly[oligo(ethylene glycol)methyl ether methacrylate]70-b-poly{oligo(ethylene glycol)methyl ether methacrylate10-co-2-methylacrylic acid 2-[(2-(dimethylamino)ethyl)methylamino]ethyl ester44} (POEGMA70-b-P(OEGMA10-co-DAMA44). Block copolymers PEO113-b-PDEA50 and POEGMA70-b-P(OEGMA10-co-DEA47-co-DPA47) were evidenced to properly condense DNA into particles with a desirable size for cellular uptake via endocytic pathways (R(H) ≈ 65-85 nm). The structure of the polyplexes was characterized in detail by scattering techniques and atomic force microscopy. The isothermal titration calorimetric data revealed that the polymer/DNA binding is endothermic; therefore, the process in entropically driven. The combination of results supports that POEGMA70-b-P(OEGMA10-co-DEA47-co-DPA47) condenses DNA more efficiently and with higher thermodynamic outputs than does PEO113-b-PDEA50. Finally, circular dichroism spectroscopy indicated that the conformation of DNA remained the same after complexation and that the polyplexes are very stable in the serum environment.
authors.affiliation: Centro de Ciências Naturais e Humanas, Universidade Federal do ABC , Santo André 09210-170, Brazil.
authors.forename: Lindomar J C
authors.initials: LJ
authors.lastname: Albuquerque
authors.affiliation: Centro de Ciências Naturais e Humanas, Universidade Federal do ABC , Santo André 09210-170, Brazil.
authors.forename: Kelly
authors.initials: K
authors.lastname: Annes
authors.affiliation: Centro de Ciências Naturais e Humanas, Universidade Federal do ABC , Santo André 09210-170, Brazil.
authors.forename: Marcella P
authors.initials: MP
authors.lastname: Milazzotto
authors.affiliation: Departamento de Biofísica, Universidade Federal de São Paulo , São Paulo 04021-001, Brazil.
authors.forename: Bruno
authors.initials: B
authors.lastname: Mattei
authors.affiliation: Departamento de Biofísica, Universidade Federal de São Paulo , São Paulo 04021-001, Brazil.
authors.forename: Karin A
authors.initials: KA
authors.lastname: Riske
authors.affiliation: Institute of Macromolecular Chemistry AS CR , 162 06 Prague, Czech Republic.
authors.forename: Eliézer
authors.initials: E
authors.lastname: Jäger
authors.affiliation: Institute of Macromolecular Chemistry AS CR , 162 06 Prague, Czech Republic.
authors.forename: Jiří
authors.initials: J
authors.lastname: Pánek
authors.affiliation: Institute of Macromolecular Chemistry AS CR , 162 06 Prague, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Štěpánek
authors.affiliation: J. Heyrovsky Institute of Physical Chemistry, 182 23 Prague, Czech Republic.
authors.forename: Peter
authors.initials: P
authors.lastname: Kapusta
authors.affiliation: Departamento de Química, Universidade Federal de Santa Maria , Santa Maria 97105-900, Brazil.
authors.forename: Paulo I R
authors.initials: PI
authors.lastname: Muraro
authors.affiliation: Departamento de Química, Universidade Federal de Santa Maria , Santa Maria 97105-900, Brazil.
authors.forename: Augusto G O
authors.initials: AG
authors.lastname: De Freitas
authors.affiliation: Departamento de Química, Universidade Federal de Santa Maria , Santa Maria 97105-900, Brazil.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Schmidt
authors.affiliation: Departamento de Química, Universidade Federal de Santa Maria , Santa Maria 97105-900, Brazil.
authors.forename: Cristiano
authors.initials: C
authors.lastname: Giacomelli
authors.affiliation: Centro de Ciências Naturais e Humanas, Universidade Federal do ABC , Santo André 09210-170, Brazil.
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Bonvent
authors.affiliation: Centro de Ciências Naturais e Humanas, Universidade Federal do ABC , Santo André 09210-170, Brazil.
authors.forename: Fernando C
authors.initials: FC
authors.lastname: Giacomelli
mesh_terms: D002151:Calorimetry; D004247:DNA / Q000737:chemistry*; D004705:Endocytosis; D018014:Gene Transfer Techniques; D006801:Humans; D008689:Methacrylates / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D009690:Nucleic Acid Conformation; D011092:Polyethylene Glycols / Q000737:chemistry*; D011109:Polymethacrylic Acids / Q000737:chemistry*; D013816:Thermodynamics
chemical_list: D008689:Methacrylates; D011109:Polymethacrylic Acids; C511861:poly(2-(diisopropylamino)ethyl methacrylate); C524499:polyethylene glycol methacrylate; D011092:Polyethylene Glycols; D004247:DNA