title: Hierarchical self-assembly of amphiphilic peptide dendrons: evolution of diverse chiral nanostructures through hydrogel formation over a wide pH range.
abstract: An amphiphilic dendron containing three dendrite L-glutamic acid units and a long alkyl chain was synthesized by a convergent method. It was found that the dendron could form hydrogels over a wide pH range from 2 to 13. Moreover, accompanying the pH change, the compounds self-assembled into various chiral structures: from helical nanotube, helical nanotube with a string of beads, and coiled superhelix to dendrite nanostructures, such as pine, feather, etc. A series of characterizations based on TEM observations, X-ray diffraction and FTIR spectroscopic measurements revealed that the dendron formed a bilayer first and then hierarchically self-assembled into various chiral nanostructures. The four carboxylic acid groups and three amide groups played an important role in the self-assembly. The interaction between the multiamide groups stabilized the bilayer structures, whereas the ionization degree of the carboxylic acids was responsible for the formation of various chiral structures. The work presented a hydrogel system with wide pH adaptability and showed the regulation on chiral structures by simple pH variations.
authors.affiliation: Beijing National Laboratory for Molecular Science, CAS Key Laboratory of Colloid Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, PR China.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Duan
authors.forename: Long
authors.initials: L
authors.lastname: Qin
authors.forename: Xuefeng
authors.initials: X
authors.lastname: Zhu
authors.forename: Minghua
authors.initials: M
authors.lastname: Liu
mesh_terms: D050091:Dendrimers / Q000737:chemistry*; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D015394:Molecular Structure; D049329:Nanostructures / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013237:Stereoisomerism; D013501:Surface-Active Agents / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D050091:Dendrimers; D010455:Peptides; D013501:Surface-Active Agents; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate