After years of research, the biotech startup Bolt Threads is debuting its lab-grown proteins in the real world.
Spider silk is one of the design industry's biggest—and most elusive—material obsessions. It's naturally lightweight, stretchy, antimicrobial, and strong. Imagine a shirt that's soft as silk, durable as steel, breathable, has a forgiving stretch, and is environmentally conscious from the start to the end of its life.
For years, we've heard that "soon" we'll farm mass quantities of spider silk, wear garments made from this wonder material, and even see it in medical applications. However, it has remained in the realm of research—actual products have yet to hit the consumer market.
That's changing today with the launch of a limited-edition synthetic spider silk tie from the Bay Area biotech company Bolt Threads.
By the appearance and feel of the tie, you'd never guess it was made in an industrial lab. It looks like a fashionable Bouclé knit you'd find in a GQ spread. Bolt Threads is only making 50 ties, each available at a cost of $314. And if a prospective buyer is ready to shell out that sum, they'll have to enter a lottery for the chance to buy one. It's more department store than science experiment, and that's exactly the point. "This marks the end of a chapter of this technology where it was all research," Dan Widmaier, Bolt Threads' CEO, says. "I see the ability to put out a fully baked, commercial product as marking the moment where were ready and able to make cooler products."
Bolt Threads grew out of research Widmaier was doing for his PhD on spider silk as a Kevlar replacement for bulletproof vests. When the startup came out of stealth mode in 2015, it was exploring applications with high-performance apparel, like sports bras. So why choose a tie—a basic wardrobe staple that people buy for looks, not function—to launch a material that's been touted for its technical qualities? For Bolt, it was about proving that its technology could be commercially viable.
The hard part isn't actually designing the garments, since these biomaterials are intended to replace fabrics like polyester, nylon, and Lycra. The challenge for the company—and for mainstreaming synthetic biomaterials generally—is in bringing down price and while boosting scale. In trying to tackle that essential part of making commercially viable biomaterials, the company chose to focus on infrastructure rather than investing R&D in a technically ambitious prototype that would never make it to market.
Widmaier plans for Bolt to both sell raw material to clothing manufacturers and also make its own goods. The company is now gearing up for a new phase: It has a durable, beautiful material and an example of what it can make. Next up? More products.
"In order for this to work, you need to be able to spin an infinite length of fiber at reproducible rates and consistent quality," Widmaier says. "You need to be able to engineer biology to make the protein at a reasonable cost, and you get a low-cost, high-quality protein source from microbial fermentation. That technology is at the bleeding edge of maturity to make that be possible. The biotech wasn't ready to five to seven years ago."
Bolt Threads synthesizes materials out of protein inspired by the DNA of different organisms. Spider silk is just one of the advanced materials and protein microfibers that the company is developing. To produce the material, Bolt first genetically modifies yeast and feeds it sugar and water in enormous fermentation tanks (much like the beer-brewing process). Then the yeast generates proteins based on the sequenced DNA of the natural protein Bolt is trying to replicate, like spider silk. Then the proteins are spun into fibers that become yarns. At this point, the material can enter a normal textile supply chain and become a knit or woven textile. Since knits require less raw material than wovens, Bolt decided to use this fabrication technique for its tie.
"Scaling up the science has been the holy grail in the realm of biofabrication," Sue Levin, a Bolt Threads' spokesperson, told me when she brought a sample of the tie to Fast Company's office. "Our fibers will never be priced competitive with polyester. It's is practically free in terms of the cost of a gram of polyester in any item you would purchase. But we'll be competitive with other fibers, including organic cotton [and silk]."
The commercialization challenge for Bolt is getting production to the scale where it can make enough yarns to produce a launch run of a product. A single tie required over 55 miles of synthesized spider-silk filament to produce. Right now the company is synthesizing protein in 800-gallon fermenters but plans to bring 53,000-gallon fermenters online later this year. This will bring raise its protein production from hundreds of pounds, as it stands now, to tons—an amount clothing producers would need to seriously consider using the material.
Right now, Bolt Threads is collaborating with Patagonia on how its biomaterials could be used in outdoor apparel. For a socially conscious company like Patagonia, the promise of synthetic proteins is particularly appealing. Many of its garments are made from synthetic fabrics and polyester, which are petroleum-based. These garments don't biodegrade and new research, some of which Patagonia has sponsored, shows that micro fibers are a leading cause of marine pollution and have even become a food supply problem. Synthetic biofabrics could provide an alternative, since protein-based microfibers could be used anywhere that polyester would normally be found.
So while a tie isn't nearly as difficult to make as a fleece jacket, it shows potential collaborators what's possible beyond a purely concept prototype. "I was stunned by how great the fabric feels, how nice and malleable it is, and how it takes color," Widmaier says. "It looks like a gorgeous product. This tells me it just isn't just a research prototype. It's a good-looking piece of apparel, but is also a demonstration of our technology. The fact that this was grown in a fermenter is astonishing to me."
While this is the Bolt's inaugural release, it is now going to a seasonal pace of introducing products either directly to consumer or with its partners. In addition to its partnership with Patagonia, Bolt is also working with a European fashion brand that designs couture and ready-to-wear garments.
"This is a beginning, not an end," Widmaier says.
Bolt is selling 50 ties at a price of $314. Visit boltthreads.com for more details.