title: "Giant surfactants" created by the fast and efficient functionalization of a DNA tetrahedron with a temperature-responsive polymer.
abstract: Copper catalyzed azide-alkyne cycloaddition (CuAAC) was employed to synthesize DNA block copolymers (DBCs) with a range of polymer blocks including temperature-responsive poly(N-isoproylacrylamide) (poly(NIPAM)) and highly hydrophobic poly(styrene). Exceptionally high yields were achieved at low DNA concentrations, in organic solvents, and in the absence of any solid support. The DNA segment of the DBC remained capable of sequence-specific hybridization: it was used to assemble a precisely defined nanostructure, a DNA tetrahedron, with pendant poly(NIPAM) segments. In the presence of an excess of poly(NIPAM) homopolymer, the tetrahedron-poly(NIPAM) conjugate nucleated the formation of large, well-defined nanoparticles at 40 °C, a temperature at which the homopolymer precipitated from solution. These composite nanoparticles were observed by dynamic light scattering and cryoTEM, and their hybrid nature was confirmed by AFM imaging. As a result of the large effective surface area of the tetrahedron, only very low concentrations of the conjugate were required in order for this surfactant-like behavior to be observed.
authors.affiliation: Department of Chemistry, University of Warwick , Coventry, West Midlands CV4 7AL, U.K.
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Wilks
authors.forename: Jonathan
authors.initials: J
authors.lastname: Bath
authors.forename: Jan Willem
authors.initials: JW
authors.lastname: de Vries
authors.forename: Jeffery E
authors.initials: JE
authors.lastname: Raymond
authors.forename: Andreas
authors.initials: A
authors.lastname: Herrmann
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Turberfield
authors.forename: Rachel K
authors.initials: RK
authors.lastname: O'Reilly
mesh_terms: D001483:Base Sequence; D004247:DNA / Q000737:chemistry*; D006358:Hot Temperature; D009682:Magnetic Resonance Spectroscopy; D018625:Microscopy, Atomic Force; D046529:Microscopy, Electron, Transmission; D009690:Nucleic Acid Conformation; D011108:Polymers / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D013501:Surface-Active Agents / Q000737:chemistry*
chemical_list: D011108:Polymers; D013501:Surface-Active Agents; D004247:DNA