Large‐Scale Assembly of Peptide‐Based Hierarchical Nanostructures and Their Antiferroelectric Properties

Abstract

organized structures enable the expression of completely different physical properties, which are absent in the basic material, and endow many biological materials with remarkable mechanical strength, [4] flexibility, [5] super-hydrophobicity, [6] and optical properties, [7] such as structural color. Therefore, many researchers have made great efforts to develop novel materials with unique physical properties and improved performance over conventional materials by mimicking these natural hierarchical structures. Although various biomaterials, such as DNA, [8] bacteriophages, [9] proteins, [10] carbohydrates, [11] and peptides, [12] are being researched and developed for this purpose, self-assembled peptide nanostructures [13] are most actively studied among them owing to their versatile properties. Diphenylalanine (FF) molecules, especially those derived from the dipeptide motif (-F19-F20-), which is a major contributing factor in amyloid fibril formation that causes Alzheimer's disease, are widely used to form peptide hierarchical nanostructures through a self-assembly process that induces the aggregation of FF molecules in water. [14] This molecular self-assembly approach enables us to build diverse peptide nanostructures with functional physical and chemical properties, including piezoelectricity, [15] ferroelectricity, [16] and photoluminescence, [17] as well as robust An effective strategy is developed to create peptide-based hierarchical nanostructures through the meniscus-driven self-assembly in a large area and fabricate antiferroelectric devices based on these nanostructures for the first time. The diphenylalanine hierarchical nanostructures (FF-HNs) are self-assembled by vertically pulling a substrate from a diphenylalanine (FF) solution dissolved in a miscible solvent under precisely controlled conditions. Owing to the unique structural properties of FF nanostructures, including high crystallinity and α-helix structures, FF-HNs possess a net electrical dipole moment, which can be switched in an external electric field. The mass production of antiferroelectric devices based on FF-HNs can be successfully achieved by means of this biomimetic assembly technique. The devices show an evident antiferroelectric to ferroelectric transition under dark conditions, while the ferroelectricity is found to be tunable by light. Notably, it is discovered that the modulation of antiferroelectric behaviors of FF-HNs under glutaraldehyde exposure is due to the FF molecules that are transformed into cyclophenylalanine by glutaraldehyde. This work provides a stepping stone toward the mass production of self-assembled hierarchical nanostructures based on biomolecules as well as the mass fabrication of electronic devices based on biomolecular nanostructures for practical applications.

Schiff Base Mediated Dipeptide Assembly toward Nanoarchitectonics

“…Since the discovery of FF self-assembled into discrete nanotubes in aqueous solution, [23] substantial research has been conducted to manipulate the self-assembly of FF into diverse functional architectures such as spherical vesicles, microtubes, microrods, nanofibrils, nanowires, and branched structures. [3,6,7,24] The polymorphism of FF-based assemblies can be influenced and facilely adjusted by changing the experimental parameters such as concentration, pH, temperature, and solvent. [25][26][27][28][29] Considering that the FF molecule has amino group in its structure, our group first explored the possibility of combining FF self-assembly with Schiff base chemistry by adding glutaraldehyde (GA) to the toluene solution.…”