The spinning processes for spider silk.

Chen, Xin; Shao, Zhengzhong; Vollrath, Fritz

This paper summarizes recent work in our groups on the factors that influence the formation of spider silks during the spinning process. The review encompasses: (a) extrusion variables that greatly affect the mechanical properties of the silk filaments; such as rate and temperature at spinning as well as the post-drawn treatment and (b) other factors affecting the conformation transition of the spider silk proteins (spidroin) such as pH and metallic ions. The observations taken together imply that the spinning process is at least as central as, and probably more important than, the composition of the 'raw' protein spinning solution. This conclusion leads us to suggest that in the future high-performance, artificial 'spider' silks may be spun from a range of solutions of silk and synthetic proteins.