A modern-day Silk Road is emerging, and traffic on it is building up.
These explorers aren’t traversing routes across continents, but instead are seeking scientific and agricultural alchemy to produce a sort of holy grail in apparel: commercial amounts of spider silk.
Spider silk is a multi-purpose fiber able to be transformed into surgical bandages, sports gear, musical strings, or body armor, says David Brigham, founder and CEO of EntoGenetics in Charlotte, NC. The military uses, in particular, motivate Brigham, a biochemist and geneticist by training. “Soldiers need better, lighter protection,” he says.
Spider silk has long been the ultimate textile target. Its beauty was coveted by royalty; Louis XIV of France supposedly had gloves, stockings, and even a full suit made from the weaves of the golden orb spider of Madagascar.
These days it’s the silk’s strength—touted as five times as strong as steel, and as tough as Kevlar but more elastic—that’s attracting attention. Stopping a runaway train from flying off the tracks using spider webs may not only be the realm of Hollywood.
But replicating that material on a scale useful for a modern-day superhero, or mere mortal, has been elusive. Spiders don’t really take to being domesticated for farm work (they get restless minutes into the “milking” process and tend toward cannibalism), so it’s difficult to harvest enough thread for a commercial apparel operation.
If it could be done, though, the stakes are huge. In the U.S. alone, the market for advanced protective gear and armor was worth $4 billion in 2010 and is expected to reach $5.2 billion next year, according to consulting firm BCC Research.
Protective gear for soldiers, as well as police and firemen, is among the top potential uses for spider silk. The fiber could also be used to make high-end performance sports apparel and, further down the line, to contribute to a host of medical applications from sutures to wound dressings. Spider silk is not rejected by the human body, so there’s also potential for artificial tendons, implant coatings, or biomedical scaffolding for organs or skin.
The question is how best to produce the material. Brigham at EntoGenetics says his team has developed a way to take the genes that allow spiders to make such strong silk and implant them into the chromosomes of silkworms, which serve as more willing factories, to produce reconstructed “spider” silk. (Spider silk is stronger, and so preferable, to that made directly by silkworms, he says.) Brigham says EntoGenetics is trying to create silk that is 100 percent from spider genes as opposed to a hybrid of spider and silkworm genes.
The North Carolina startup has plenty of competition. Kraig Biocraft Laboratories in Lansing, MI, is also trying to produce spider silk through transgenic silkworms to make a fiber that is a composite material. “It’s spider DNA spliced into the silkworm so the silkworm produces spider protein but also produces its own proteins,” says Kim Thompson, Kraig Labs’ founder and CEO.
The result, he says, is
