“…Keratins are versatile proteins for the production of flexible films, sponges, fibers, and nanofibers. In particular, pure keratin can be transformed into nanofibers by electrospinning from solutions of solvents, such as formic acid [88] and 1,1,1,3,3,3-hexafluoro-2-propanol [53]; on the contrary, keratin-based nanofibers have been obtained from water solutions by the addition of synthetic water-soluble polymers, like poly(ethyl oxide) [89], polyvinyl alcohol [90], polyvinylpyrrolidone [91], and polycaprolactone [53].…”