title: Monodisperse Cylindrical Micelles and Block Comicelles of Controlled Length in Aqueous Media.
abstract: Cylindrical block copolymer micelles have shown considerable promise in various fields of biomedical research. However, unlike spherical micelles and vesicles, control over their dimensions in biologically relevant solvents has posed a key challenge that potentially limits in depth studies and their optimization for applications. Here, we report the preparation of cylindrical micelles of length in the wide range of 70 nm to 1.10 μm in aqueous media with narrow length distributions (length polydispersities <1.10). In our approach, an amphiphilic linear-brush block copolymer, with high potential for functionalization, was synthesized based on poly(ferrocenyldimethylsilane)-b-poly(allyl glycidyl ether) (PFS-b-PAGE) decorated with triethylene glycol (TEG), abbreviated as PFS-b-(PEO-g-TEG). PFS-b-(PEO-g-TEG) cylindrical micelles of controlled length with low polydispersities were prepared in N,N-dimethylformamide using small seed initiators via living crystallization-driven self-assembly. Successful dispersion of these micelles into aqueous media was achieved by dialysis against deionized water. Furthermore, B-A-B amphiphilic triblock comicelles with PFS-b-poly(2-vinylpyridine) (P2VP) as hydrophobic "B" blocks and hydrophilic PFS-b-(PEO-g-TEG) "A" segments were prepared and their hierarchical self-assembly in aqueous media studied. It was found that superstructures formed are dependent on the length of the hydrophobic blocks. Quaternization of P2VP was shown to cause the disassembly of the superstructures, resulting in the first examples of water-soluble cylindrical multiblock comicelles. We also demonstrate the ability of the triblock comicelles with quaternized terminal segments to complex DNA and, thus, to potentially function as gene vectors.
authors.affiliation: School of Chemistry, University of Bristol , Bristol BS8 1TS, United Kingdom.
authors.forename: Ali
authors.initials: A
authors.lastname: Nazemi
authors.affiliation: School of Chemistry, University of Bristol , Bristol BS8 1TS, United Kingdom.
authors.forename: Charlotte E
authors.initials: CE
authors.lastname: Boott
authors.affiliation: School of Chemistry, University of Bristol , Bristol BS8 1TS, United Kingdom.
authors.forename: David J
authors.initials: DJ
authors.lastname: Lunn
authors.affiliation: School of Chemistry, University of Bristol , Bristol BS8 1TS, United Kingdom.
authors.forename: Jessica
authors.initials: J
authors.lastname: Gwyther
authors.affiliation: School of Chemistry, University of Bristol , Bristol BS8 1TS, United Kingdom.
authors.forename: Dominic W
authors.initials: DW
authors.lastname: Hayward
authors.affiliation: H. H. Wills Physics Laboratory, University of Bristol , Bristol BS8 1TL, United Kingdom.
authors.forename: Robert M
authors.initials: RM
authors.lastname: Richardson
authors.affiliation: Department of Chemistry, University of Toronto , Toronto, Ontario M5S 3H6, Canada.
authors.forename: Mitchell A
authors.initials: MA
authors.lastname: Winnik
authors.affiliation: School of Chemistry, University of Bristol , Bristol BS8 1TS, United Kingdom.
authors.forename: Ian
authors.initials: I
authors.lastname: Manners
mesh_terms: D004852:Epoxy Compounds / Q000737:chemistry; D008823:Micelles; D008958:Models, Molecular; D011092:Polyethylene Glycols / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D011137:Polystyrenes / Q000737:chemistry; D011145:Polyvinyls / Q000737:chemistry; D011725:Pyridines / Q000737:chemistry
chemical_list: D004852:Epoxy Compounds; D008823:Micelles; D011108:Polymers; D011137:Polystyrenes; D011145:Polyvinyls; D011725:Pyridines; C557737:poly(isoprene-b-styrene-b-2-vinyl pyridine); C028914:triethylene glycol; D011092:Polyethylene Glycols; C054361:allyl glycidyl ether