High stability of self‐assembled peptide nanowires against thermal, chemical, and proteolytic attacks

Abstract

Understanding the self-assembly of peptides into ordered nanostructures is recently getting much attention since it can provide an alternative route for fabricating novel bio-inspired materials. In order to realize the potential of the peptide-based nanofabrication technology, however, more information is needed regarding the integrity or stability of peptide nanostructures under the process conditions encountered in their applications. In this study, we investigated the stability of self-assembled peptide nanowires (PNWs) and nanotubes (PNTs) against thermal, chemical, proteolytic attacks, and their conformational changes upon heat treatment. PNWs and PNTs were grown by the self-assembly of diphenylalanine (Phe-Phe), a peptide building block, on solid substrates at different chemical atmospheres and temperatures. The incubation of diphenylalanine under aniline vapor at 150 degrees C led to the formation of PNWs, while its incubation with water vapor at 25 degrees C produced PNTs. We analyzed the stability of peptide nanostructures using multiple tools, such as electron microscopy, thermal analysis tools, circular dichroism, and Fourier-transform infrared spectroscopy. Our results show that PNWs are highly stable up to 200 degrees C and remain unchanged when incubated in aqueous solutions (from pH 1 to 14) or in various chemical solvents (from polar to non-polar). In contrast, PNTs started to disintegrate even at 100 degrees C and underwent a conformational change at an elevated temperature. When we further studied their resistance to a proteolytic environment, we discovered that PNWs kept their initial structure while PNTs fully disintegrated. We found that the high stability of PNWs originates from their predominant beta-sheet conformation and the conformational change of diphenylalanine nanostructures. Our study suggests that self-assembled PNWs are suitable for future nano-scale applications requiring harsh processing conditions.

Entrap and release of Phe–Phe nanotubes in sol–gel derived silicate matrix: study through nanosilver interaction

“…However, one-dimensional structures like tubes, wires, ribbons, and fibers have been the most commonly found morphologies in these systems. Phe-Phe nanotubes (NTs) exhibit several special properties such as consistent homogeneity along the length and stability at high temperatures and enzymatic conditions [9]. Currently, it has been reported that these structures have potential applications in the design of optical wave-guiding [10] and drug delivery materials [11].…”

Mineralization of Self‐assembled Peptide Nanofibers for Rechargeable Lithium Ion Batteries

“…[ 16 , 17 ] Among numerous self-assembling peptides reported to date, diphenylalanine (Phe-Phe, FF) and its derivatives [18][19][20][21][22][23][24][25][26][27][28][29][30] are simplest peptides exhibiting unique mechanical, [ 19 ] electrochemical, [ 20 ] and optical properties [ 21 ] as well as high thermal and chemical stabilities. [ 23 ] It has been reported that they can readily form various nanostructures, including nanotubes, [18][19][20][21][22] nanowires, [23][24][25][26][27] nanospheres, [ 28 ] organogels, [ 29 ] and hydrogels [ 30 ] through a self-assembly process. Here, we fi rst report the synthesis of transition metal phosphate nanotubes for application as a cathode material for rechargeable lithium (Li) ion batteries by using a peptide hydrogel self-assembled from fl uorenylmethoxycarbonyl (Fmoc)-FF [ 30 ] as a template.…”

Piezoelectricity and ferroelectricity in biomaterials: Molecular modeling and piezoresponse force microscopy measurements

“…14(a), cooling branch): in this case, without an applied electric field, we have vanishing value of the total dipole moment due to full compensation of individual moments. It should be stated here that, according to Ryu and Park, 85 some additional structural transformation could occur under the prolonged annealing above 150…”