Wool Keratin Photolithography as an Eco-Friendly Route to Fabricate Protein Microarchitectures.

Herein, we present an eco-friendly route to construct protein microarchitectures by using wool keratin (WK) as a green biophotoresist. The photoactive WK was extracted from wool with a method of alkaline hydrolysis and reacted with 2-isocyanatoethyl methacrylate (IEM). The whole process can avoid the use of surfactant and does not cause apparent changes in the structure and function of WK. With the aid of direct-write photolithography, "photoresist-like" WK can be further used for fabricating well-defined and high-performance patterns at a low micron-scale (μm) without high temperature, complicated process, long time, and high production cost.