Self-assembled amphiphiles transmission electron microscopy

Goldraich M, Talmon Y (2000) Direct-imaging cryo-transmission electron microscopy in the study of colloids and polymer solutions. In Alexandridis P, Lindman B (eds) Amphiphilic block copolymers self assembly and applications. Elsevier, Amsterdam... 

Figure 14.10 Self-assembly of peptide-amphiphiles into nanofibers (a) a peptide amphi-phile molecule with five distinct regions designed for hydroxyapatite mineralization, (b) a schematic of molecular self-assembly, and (c) a negatively stain transmission electron microscopy image of the nanofibers. Reprinted from Hartgerink et al. (2001). Copyright 2001 American Association for the Advancement of Science.

Figm 13 (a) Sequence and schematic representation of the self-assembly of an amphiphilic diblock elastin polypeptide into core-shell nanoparticles. Elastin-mimetic protein polymers that comprise fusions of elastin sequences with different 7, values can be induced to undergo self-assembly at a temperature between the two transition temperatures, (b) Differential scanning calorimetry measurements indicate an endothermic transition for the more hydrophobic (lower 7 block with a value that corresponds to those observed for the burial of hydro-phobic residues within a folded protein, (c) This transition coincides with the formation of spherical assemblies in which the more hydrophobic block is confined within the micellar core. Transmission electron microscopy measurements are consistent with spherical micelles and more complex assemblies. Reprinted from Lee, T. A. T. Cooper, A. Apkarian, R. P. Conticello, V. P. Adv. Mater. 2000, f2(15), Copyright 2000, with... 

Figure 18). Unexpectedly, an LC phase was detected for the nonglobally amphipathic helix of -peptide A. To understand this uniqne feature of A to form an LC phase in aqueous solution, Gelhnan and coworkers systematically studied the contribution of the different side chains of A to the intermolecnlar interactions. It was disclosed that the presence of aromatic residues in the nonglobally amphiphilic -peptide plays a crucial role in the formation of the LC phase in water. They also found that the reduction in the net charge of the peptides led to the enhancement of LC phases. In addition, cryo-TEM (transmission electron microscopy) provided evidence that liquid crystallinity of -peptide A results from its self-assembly into nanofibers. 

---