Summary: A novel human hair protein hybrid fiber was developed by combining (i) the high‐efficiency extraction technique for preparing human hair proteins and (ii) the watery hybridization spinning method using gellan and chitosan. The resulting human hair protein‐gellan‐chitosan hybrid fibers are conveniently produced by simply mixing the 7–35 wt.‐% human hair protein‐1.0 wt.‐% gellan aqueous solution and the 1.0 wt.‐% chitosan‐0.15 M acetic acid solution at 50 °C, followed by pulling out to spin the human hair protein‐gellan‐chitosan ternary complex thus formed at the aqueous solution interface. By use of this simple procedure and ambient spinning condition, the human hair proteins were successfully incorporated into the fiber matrix of gellan‐chitosan, without any denaturation and degradation. The hybrid fiber can also be recognized as a new type of the regenerated human hair keratin fiber, because of its high purity and content of human hair keratin types I and II. Mechanical strength of the human hair protein‐gellan‐chitosan fiber varies from 108 to 153 MPa, depending on the contents of the human hair proteins. SEM observation revealed that the incorporated human hair proteins were found as the particles (1–10 μm) on the fiber surface. The type I and II keratins in the fiber matrices were rapidly biodegraded by chymotrypsin within 30 min, and the digested fragments slowly released from the fiber matrices. Thus, the human hair hybrid fiber is a very promising material to have a broad spectrum of applications as the engineering fibers, particularly for the medical uses, because the human hair proteins are easily available, biocompatible, and bioresorbable materials.
Gellan‐chitosan hybrid fiber (a), human hair protein‐gellan‐chitosan hybrid fiber (b).
