Title
Tubular Network Formation by Mixing Amphiphilic Polypeptides with Differing Hydrophilic Blocks
Author
Md. Mofizur Rahman, Motoki Ueda, Kon Son, Siyoong Seo, Shinji Takeoka, Takuji Hirose, Yoshihiro Ito
Year
2019
Journal
Biomacromolecules
Abstract
Artificial tubular networks are promising structures for biomaterial applications because of their large surface areas. A tubular network was formed by co-assembling two different amphiphilic polypeptides, poly(ethylene glycol)-b-(l-Leu-Aib)6 (PL12) and polysarcosine-b-(l-Leu-Aib)6 (SL12). They both have the same hydrophobic 12-mer helical block (l-Leu-Aib)6 but different hydrophilic chains, poly(ethylene glycol) and polysarcosine. In water, both polypeptides self-assembled into a tubular structure having a uniform 80 nm diameter that was formed by packing among the hydrophobic L12 blocks. The SL12 nanotubes were short (200 nm), straight, and robust. PL12 formed long (>1 μm), bendable, and fusogenic nanotubes. The amphiphiles were then co-assembled with various mixing ratios to form tubular networks. Higher concentrations of PL12 made the nanotubes more bendable and fusogenic between open tube ends, which produced branching junctions under heat treatment.
Instrument
J-1500, FP-6500
Keywords
Circular dichroism, Secondary structure, Chemical stability, Biochemistry