Covalent Capture of Aligned Self-Assembling Nanofibers.

Area of Science:

• Supramolecular chemistry
• Biomaterials science
• Nanotechnology

Background:

• Multidomain peptides spontaneously assemble into nanofibers for biomedical applications.
• Previous work demonstrated reversible assembly and utility in drug and cell delivery.
• Control over self-assembly was limited to disorganized nanofibers.

Purpose of the Study:

• To manipulate multidomain peptide assembly into parallel-aligned fiber bundles.
• To investigate the role of DOPA in controlling fiber alignment and stability.
• To enhance the structural integrity and properties of self-assembled nanofibers.

Main Methods:

• Utilizing shear forces during syringe delivery to induce fiber alignment.
• Incorporating the amino acid DOPA (3,4-dihydroxyphenylalanine) into peptide sequences.
• Analyzing self-assembled structures using scanning electron microscopy and birefringence measurements.
• Inducing covalent linkage through DOPA oxidation to stabilize aligned bundles.

Main Results:

• Achieved parallel-aligned nanofiber bundles dependent on peptide sequence and shear stress.
• DOPA incorporation enabled the formation of anisotropic hydrogel strings with significant birefringence.
• Scanning electron microscopy confirmed highly aligned nanofibers within the hydrogel string.
• Covalent crosslinking via DOPA oxidation enhanced structural integrity and birefringence of the aligned bundles.

Conclusions:

• Multidomain peptides, particularly with DOPA, can form aligned nanofiber structures under shear stress.
• DOPA-induced covalent crosslinking improves the stability and optical properties of these aligned assemblies.
• This controlled assembly offers new possibilities for advanced biomaterials and biomedical applications.