Size-Dependent Isotropic/Nematic Phase Transition Behavior of Liquid Crystalline Peptide Nanowires

• Published in: Macromolecular chemistry and physics Vol. 210; no. 16; pp. 1283 - 1290
• Main Authors: Park, Ji Sun, Han, Tae Hee, Oh, Jun Kyun, Kim, Sang Ouk
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 21.08.2009; WILEY‐VCH Verlag; Wiley
• Subjects: Aminoacids, peptides. Hormones. Neuropeptides; Analytical, structural and metabolic biochemistry; Applied sciences; Assemblies; Biological and medical sciences; colloids; Dispersions; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; Liquid crystals; Nanowires; Natural polymers; Nematic; Peptides; Phase transformations; Physicochemistry of polymers; Proteins; self-assembly; Solvents; Self assembly; Phase diagram; peptides; Experimental study; Dimension spectrum; colloids; Liquid crystals; Phase transitions; self-assembly; Carbon disulfide; Dipeptides; Electrokinetic potential; Nanowires
• ISSN: 1022-1352; 1521-3935
• DOI: 10.1002/macp.200900202

We present size‐tunable assemblies of peptide nanowires and study their liquid crystalline phase behavior. An aromatic peptide molecule of diphenylalanine was rapidly assembled into one‐dimensional nanowires, whose sizes were tunable according to the initial concentration of diphenylalanine in the preparing solution. The stable dispersion of peptide nanowires in an organic solvent exhibited colloidal nematic liquid crystalline phases. The liquid crystalline phase transition was governed by the repulsive electrostatic interaction among peptide nanowires as well as their shape anisotropy and polydispersity. Our work provides an interesting model system to investigate the liquid crystalline phase behaviors of a biomolecular assembly in terms of its assembled morphology and intermolecular interactions. Size‐tunable assemblies of peptide nanowires and their corresponding colloidal liquid crystalline phase behavior are presented. The stable dispersion of peptide nanowires having various sizes exhibits nematic liquid crystalline phases in a non‐polar organic solvent. The detailed experimental analysis reveals that the phase transition behavior is governed by the electrostatic interaction among peptide nanowires as well as the shape and size of nanowires.