BioSteel was a trademark name for a high-strength fiber-based material made of the recombinant spider silk-like protein extracted from the milk of transgenic goats, made by defunct Montreal-based company Nexia Biotechnologies, and later by the Randy Lewis lab of the University of Wyoming and Utah State University. It is reportedly 7-10 times as strong as steel if compared for the same weight, and can stretch up to 20 times its unaltered size without losing its strength properties. It also has very high resistance to extreme temperatures, not losing any of its properties within −20 to 330 degrees Celsius (−4 to 626 degrees Fahrenheit).
The company had created lines of goats to produce recombinant versions of two spidroins from Nephila clavipes, the golden orb weaver, MaSp1 and MaSp2 When the female goats lactate, the milk, containing the recombinant DNA silk, was to be harvested and subjected to chromatographic techniques to purify the recombinant silk proteins.
The purified silk proteins could be dried, dissolved using solvents (DOPE formation) and transformed into microfibers...