Fast Self‐Assembly Dynamics of a β‐Sheet Peptide Soft Material

Abstract

Peptide‐based hydrogels are promising biocompatible materials for wound healing, drug delivery, and tissue engineering applications. The physical properties of these nanostructured materials depend strongly on the morphology of the gel network. However, the self‐assembly mechanism of the peptides that leads to a distinct network morphology is still a subject of ongoing debate, since complete assembly pathways have not yet been resolved. To unravel the dynamics of the hierarchical self‐assembly process of the model β‐sheet forming peptide KFE8 (Ac‐FKFEFKFE‐NH2), high‐speed atomic force microscopy (HS‐AFM) in liquid is used. It is demonstrated that a fast‐growing network, based on small fibrillar aggregates, is formed at a solid–liquid interface, while in bulk solution, a distinct, more prolonged nanotube network emerges from intermediate helical ribbons. Moreover, the transformation between these morphologies has been visualized. It is expected that this new in situ and in real‐time methodology will set the path for the in‐depth unravelling of the dynamics of other peptide‐based self‐assembled soft materials, as well as gaining advanced insights into the formation of fibers involved in protein misfolding diseases.

Resolving the nanoscale structure of β-sheet assemblies using single-molecule orientation-localization microscopy

“…S12 for more examples). Recently, branching has also been observed using high-speed atomic force microscopy 50 , but to our knowledge, enclosed, looping structures have never been reported. SMOLM images (Fig.…”

“…The left-handed helical supramolecular structure of KFE8 L was first observed using AFM and TEM over 20 years ago 35 , and molecular dynamics simulations suggest that the complementary amphipathic βstrands of KFE8 form a bilayer, i.e., a helical ribbon 35,49 . Since then, the putative helical ribbon model has been widely accepted 36,[50][51][52] . To date, no further direct experimental validation has been realized.…”

Hybrid Self-Assembled Peptide Hydrogels Promote Skin Wound Healing in Diabetic Mice

“…The peptides are composed of a specific arrangement of hydrophilic amino acids (K and E) and hydrophobic amino acids (F), which are structured in a β-sheet conformation . Nanofiber architectures can be formed through the self-assembly of the F–Q and F–G peptides, which is driven by hydrophilic and hydrophobic effects (Scheme ).…”

Mechanisms and influencing factors of peptide hydrogel formation and biomedicine applications of hydrogels

“…By hydrogen bonding between peptides, peptides can self-assemble into nanofibers. 21 After the initial formation of peptide nanofibers, the self-assembly behavior will occur continuously. By the extension and entanglement of the nanofibers, the final 3D network hydrogel can be obtained.…”