Self-assembly and supramolecular transition of poly(amidoamine) dendrons focally modified with aromatic chromophores.
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.
Wang
Bing-Bing
BB
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.
Li
Wu-Song
WS
Jia
Xin-Ru
XR
Gao
Min
M
Ji
Yan
Y
Zhang
Xin
X
Li
Zi-Chen
ZC
Jiang
Lei
L
Wei
Yen
Y
D003124:Colorimetry; D050091:Dendrimers / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D015394:Molecular Structure; D009757:Nylons / Q000737:chemistry*; D014961:X-Ray Diffraction
D050091:Dendrimers; D009757:Nylons; C520550:PAMAM-G4