In the late 1990s, Nexia Biotechnologies made headlines with its development of BioSteel, an artificial spider silk that reportedly outperformed Kevlar in terms of strength and durability. BioSteel’s method of manufacture, which involved the growth of spider silk protein in transgenic goats’ milk, was even more provocative than the product itself. Although Nexia went bankrupt by 2009, the dream of a biocompatible, ultrahigh performance fiber—described by the Wall Street Journal as “the Holy Grail in biomimicry”— lives on.
The Japanese company Spiber recently announced its ability to fabricate synthetic spider thread with the tensile strength of steel. Spiber doesn’t use transgenic goats; rather, it produces the required recombinant DNA for spider-silk proteins via bioengineered bacteria. After converting these proteins into a dry powder, the manufacturer generates threads by extruding the proteins from a hollow, super-thin needle.
Spiber’s silk exhibits impressive performance: a 4 millimeter diameter bundle of threads can support the weight of a grown man. The company has aggressive plans to bring its product to market, and intends to manufacture one metric ton of the silk—to be used in applications ranging from bulletproof vests to biocompatible wound closure systems—by 2015. Spiber faces tough competition from other companies such as Germany’s AMSilk and Michigan’s Kraig Biocraft Labs, which is a good indication that this “Holy Grail” may be within reach.
