title: Self-assembly and supramolecular transition of poly(amidoamine) dendrons focally modified with aromatic chromophores.
abstract: Three novel series of amphiphiles based on poly(amidoamine) dendrons (from G1 to G3) and having different aromatic chromophores (Cz I, Cz II, and Py) at the focal point were synthesized and studied for their self-assembly behavior in aqueous solution by using electronic microscopies (i.e., SEM and TEM), UV-vis, fluorescence, IR, and (1)H NMR spectroscopy. It was found that the generation of dendrons affected significantly the self-assembly of these amphiphiles in aqueous solution and the morphological structures of the resulting assemblies depended greatly on the architecture of the focal chromophores. As a result, the first generation of dendrons assembled readily into vesicles at low concentrations. These vesicular structures subsequently fused to form a stable tubular structure. Similar tubular structures could also be directly obtained through self-assembly of these amphiphilic dendrons at high concentrations. X-ray investigations showed that the resulting tubules possessed a lamellar structure. A head-to-head packing model of amphiphilic dendrons in the assemblies was proposed.
authors.affiliation: Department of Polymer Science and Engineering, Key Laboratory of Polymer Chemistry and Physics of the Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
authors.forename: Bing-Bing
authors.initials: BB
authors.lastname: Wang
authors.forename: Wu-Song
authors.initials: WS
authors.lastname: Li
authors.forename: Xin-Ru
authors.initials: XR
authors.lastname: Jia
authors.forename: Min
authors.initials: M
authors.lastname: Gao
authors.forename: Yan
authors.initials: Y
authors.lastname: Ji
authors.forename: Xin
authors.initials: X
authors.lastname: Zhang
authors.forename: Zi-Chen
authors.initials: ZC
authors.lastname: Li
authors.forename: Lei
authors.initials: L
authors.lastname: Jiang
authors.forename: Yen
authors.initials: Y
authors.lastname: Wei
mesh_terms: D003124:Colorimetry; D050091:Dendrimers / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D015394:Molecular Structure; D009757:Nylons / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D050091:Dendrimers; D009757:Nylons; C520550:PAMAM-G4