Biomacromolecules. 2018 Aug 13;19(8):3445-3455. doi: 10.1021/acs.biomac.8b00762. Epub 2018 Jul 12.
Secondary-Structure-Mediated Hierarchy and Mechanics in Polyurea-Peptide Hybrids
Lindsay E Matolyak, Chase B Thompson, Bingrui Li, Jong K Keum, Jonathan E Cowen, Richard S Tomazin, LaShanda T J Korley
Abstract
Peptide-polymer hybrids combine the hierarchy of biological species with synthetic concepts to achieve control over molecular design and material properties. By further incorporating covalent cross-links, the enhancement of molecular complexity is achieved, allowing for both a physical and covalent network. In this work, the structure and function of poly(ethylene glycol) (PEG)-network hybrids are tuned by varying peptide block length and overall peptide content. Here the impact of poly(ε-carbobenzyloxy-l-lysine) (PZLY) units on block interactions and mechanics is explored by probing secondary structure, PEG crystallinity, and hierarchical organization. The incorporation of PZLY reveals a mixture of α-helices and β-sheets at smaller repeat lengths ( n = 5) and selective α-helix formation at a higher peptide molecular weight ( n = 20). Secondary structure variations tailored the solid-state film hierarchy, whereby nanoscale fibers and microscale spherulites varied in size depending on the amount of α-helices and β-sheets. This long-range ordering influenced mechanical properties, resulting in a decrease in elongation-at-break (from 400 to 20%) with increasing spherulite diameter. Furthermore, the reduction in soft segment crystallinity with the addition of PZLY resulted in a decrease in moduli. It was determined that, by controlling PZLY content, a balance of physical associations and self-assembly is obtained, leading to tunable PEG crystallinity, spherulite formation, and mechanics.
Related products
Abbreviation: H2N-PEG-NH2
Name: α,ω-Diamino poly(ethylene glycol)
For more product information, please contact us at:
US Tel: 1-844-782-5734
US Tel: 1-844-QUAL-PEG
CHN Tel: 400-918-9898
Email: sales@sinopeg.com
