Abstract
Peptide based nano-assemblies with their self-organizing ability has shown lot of promise due to their high degree of thermal and chemical stability, for biomaterial fabrication. Developing an effective way to control the organization of these structures is important for fabricating application-oriented materials at the molecular level. The present study reports the impact of electric and magnetic field-mediated perturbation of the self-assembly phenomenon, upon the chemical and structural properties of diphenylalanine assembly. Our studies show that, electric field effectively arrests aggregation and self-assembly formation, while the molecule is allowed to anneal in the presence of applied electric fields of varying magnitudes, both AC and DC. The electric field exposure also modulated the morphology of the self-assembled structures without affecting the overall chemical constitution of the material. Our results on the modulatory effect of the electric field are in good agreement with theoretical studies based on molecular dynamics reported earlier on amyloid forming molecular systems. Furthermore, we demonstrate that the self-assemblies formed post electric-field exposure, showed difference in their crystal habit. Modulation of nano-level architecture of peptide based model systems with external stimulus, points to a potentially rewarding strategy to re-work proven nano-materials to expand their application spectrum.
Highlights
In last decade, there has been an increased focus on organic and bio-organic nano-assemblies
The control sample with no field, and the sample cooled under magnetic field (0.6 T), showed visible nano-assemblies, which was further confirmed by light scattering and Field Emission Scanning Electron Microscopy (FE-SEM) experiment
We demonstrated that electric field could arrest the hierarchical self-assembly of diphenylalanine, and self-assembly was initiated only after the withdrawal of external electric field whereas magnetic field at the experimental (0.6 T) range has no significant effect on assembly formation
Summary
There has been an increased focus on organic and bio-organic nano-assemblies. FF incidentally is the core recognition motif of the β-amyloid polypeptide, a peptide associated with Alzheimer’s disease[1] It can self-assemble into a variety of structures like microtubes, nanotubes[2], microcrystals, nanofibers[3], nanorods[4, 5] and nanowires[6]. Andrij Baumketner in a recent study, explored the feasibility of using external electric field to disaggregate amyloid fibrils, by inducing folding into an α-helical state reducing their β sheet conformation[38]. This is especially important because FF is the core recognition motif of β-amyloid segment. Our results indicate that field induced perturbation approach can be a promising tool for controlling nano-assembly, generating novel architectures
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
