Charged Diphenylalanine Nanotubes and Controlled Hierarchical Self-Assembly

Abstract

Hexagonal hierarchical microtubular structures are produced by diphenylalanine self-assembly and the ratio of the relative humidity in the growth chamber to the diphenylalanine concentration (defined as the RH-FF ratio) determines the microtubular morphology. The hexagonal arrangement of the diphenylalanine molecules first induces the hexagonal nanotubes with opposite charges on the two ends, and the dipolar electric field on the nanotubes serves as the driving force. Side-by-side hexagonal aggregation and end-to-end arrangement ensue finally producing a hexagonal hierarchical microtubular structure. Staining experiments and the external electric field-induced parallel arrangement provide evidence of the existence of opposite charges and dipolar electric field. In this self-assembly, the different RH-FF ratios induce different contents of crystalline phases. This leads to different initial nanotube numbers finally yielding different microtubular morphologies. Our calculation based on the dipole model supports the dipole-field mechanism that leads to the different microtubular morphologies.

Peptide Self-Assembled Nanostructures for Drug Delivery Applications

“…It has been recognized as the core recognition motif to drive selfassembly in Alzheimer's disease. Many studies have been carried out to self-assemble FF dipeptides into different nanostructures including nanoparticles, nanotubes, nanovesicles, and nanowires, shown in Figure 2 [34,[38][39][40][41][42]. FF selfassembled nanotubes have been demonstrated to be thermally stable, which is one of the most unique properties for bioinspired materials [43].…”

Novel method for prediction of micro/nanostructures of diphenylalanine dipeptide based on semiempirical thermodynamic study

“…The cationic or anionic species are dominant at values of pH much smaller or higher than the isoelectric point (pI), respectively. The pH of the solution under study is near the pI (=5.5 [6]), and the dipeptide are mainly in the zwitterion form [12]. The physical activity coefficient of the dipeptide can be described by the various models available in the literatures for aqueous nonelectrolyte and electrolyte solutions.…”

“…These processes are affected by dominant parameters as the degree of supersaturation, the level of active impurities, and pH of the aqueous solution. Wang et al [12] investigated implicitly the effect of impurities on the morphological evolution of the dipeptide. Han et al [11] and Martins et al [13] considered the effect of pH on the hierarchal assembly of the dipeptide and on the morphological control of the dipeptide nanotubes, respectively.…”

Effect of noncovalent interaction on the self-assembly of a designed peptide and its potential use as a carrier for controlled bFGF release

“…1 Inspired by nature, a variety of biomolecules, including amino acids, [2][3][4] peptides, [5][6][7][8] proteins, 9,10 DNA, 11 saccharides, 12 lipids, 13,14 and their derivatives, [15][16][17] have been used as versatile building blocks for the design of functional structures at the nanoscale and microscale through molecular self-assembly. Building blocks have unique physical and chemical properties, which, if harnessed effectively, can result in materials with highly functional characteristics.…”