Electrospinning Induced Orientation of Protein Fibrils.

Amyloid-like fibrils are prepared from protein in the lab by controlled heat treatments, yet these must be further assembled to match the desirable mechanical and structural properties of biological fibers. Here, β-lactoglobulin fibrils were incorporated into poly(ethylene oxide) fibers of 40-180 nm diameter by electrospinning. Protein fibrils presented as short segments dispersed within electrospun fibers, with no change in fibril diameter after electrospinning. Imaging analysis revealed fibrils were aligned within 20° relative to the fiber long axis, and alignment was further confirmed by polarized FTIR and anisotropic SAXS/WAXS scattering patterns. The elastic modulus of fibers increased with protein fibril content from 0.8 to 2 GPa, which is superior to reported values of silk, collagen, and gelatin. The present setup allows for manufacture of large quantities of polymeric fibers containing protein fibrils with varied diameter and mechanical strength, endowing great potential for a variety of applications.