Fabrication of Nano/micro-fiber Materials from Rigid Rod Peptide Chains via Electrospinning and Their Mechanical Properties*

Peptides are ideal candidates for the design and controlled assembly of nanoscale materials due to their potential to assemble with almost atomistic precision as in biological systems. The ability to create rigid rod chains composed of individual peptide bundles and to develop nano/microfibers containing the stiff chains offers the opportunity to develop unique structural features and a remarkable combination of high stiffness, high strength, large elasticity and elongation. This study is to facilitate nano/microfiber electrospinning, focusing on the use of synthetic peptides and to measure initial physical properties of peptide-based fibers. Computationally-designed peptides formed designed coiled coil bundles that serve as supramolecular monomers in chain formation. The bundle chains, or “bundlemers” display rigid-rod character due to intrabundle and interbundle physical and covalent interactions. The resultant rigid chains are employed to fabricate nano/micro-fibers via electrospinning. The mechanical properties of electrospun rod fibers are investigated as a function of bundlemer rod length, intra- or inter-chain interactions (both before and/or after electrospinning), and bundle type included in the bundlemer chains.