Optimizing and Evaluating Hand-drawing and Wet-spinning for Recombinant Spider Silk Fiber Production

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Textile Engineering

Background:

• Spider silks exhibit exceptional mechanical properties, including high strength and toughness.
• Natural silk production is limited, driving interest in recombinant spider silk production.
• Recombinant production allows for protein customization and scalable material generation.

Purpose of the Study:

• To establish a comprehensive protocol for evaluating the spinnability of recombinant spider silk proteins.
• To compare hand-drawing and wet-spinning techniques for silk fiber formation.
• To provide a framework for optimizing spinning conditions and characterizing fiber properties.

Main Methods:

• Preparation of high-concentration protein solutions ('spinning dope') from purified silk proteins.
• Hand-drawing and wet-spinning methods for fiber fabrication.
• Characterization techniques including optical microscopy, polarized light microscopy, tensile testing, and FTIR spectromicroscopy.

Main Results:

• The protocol successfully evaluated various recombinant spider silk proteins, including those based on aciniform, pyriform, and major ampullate silks.
• Optimization of spinning dope conditions and post-spin drawing modulated fiber properties.
• Characterization revealed insights into fiber diameter, alignment, mechanical strength, and secondary structure.

Conclusions:

• The developed protocol is effective for assessing recombinant spider silk protein suitability for fiber spinning.
• The methodology allows for customization of spinning parameters to achieve desired fiber characteristics.
• This work facilitates the development of advanced biomaterials from engineered spider silks.