Spider silk five times stronger than steel, silkworms boiled alive by the trillion, and biotech fibers now appearing on the runway — here is the full, complicated picture of silk’s next chapter.
That silk scarf your grandmother gave you is one of your most prized possessions — and for good reason. It drapes like nothing else in your closet, holds color with a luminosity that shifts with the light, and carries a history most fabrics could spend centuries trying to accumulate. Silk has been seducing humans for roughly 5,000 years, and its physical qualities — biodegradable, temperature-regulating, naturally protein-based — remain genuinely difficult to replicate. What tends to get far less attention is how it’s made: conventional silk kills approximately 3,000 silkworms per pound of fabric, and an estimated 1.2 trillion are killed annually in a process that has quietly gone unquestioned while fur and leather faced decades of public scrutiny. A generation of bioengineers, geneticists, and material scientists — working from a renovated Pittsburgh firehouse to the silk belts of Vietnam — is building something designed to change that conversation: silk’s scientific successor, and, depending on the approach, a more ethically accountable one.
Spider silk, the material at the center of this innovation, has held researchers in something close to obsession for decades. Pound for pound, it combines strength and elasticity unlike anything else in the known world, natural or synthetic. Five times stronger than steel by weight but entirely organic, it is, as Fiorenzo Omenetto, director of the Silklab at Tufts University in Massachusetts, puts it, “the stuff of superheroes.” It shares rare company with graphene and Kevlar — materials with extraordinary physical properties — except those require synthetic chemicals to produce. Spider silk could theoretically do what they do, possibly better, and organically. The challenge has always been the spiders themselves: cannibalistic by nature, they cannot be farmed at any meaningful scale, which is why the most promising recent work focuses on making their silk without them.
Silk 2.0 is already on the runway
Spiber, the Japanese biotech company founded in 2007, has perhaps moved fastest from laboratory to retail floor. Its Brewed Protein fiber is produced through microbial fermentation using plant-derived raw materials — no silkworms, no spiders, no animal involvement at all. Its manufacturing facility in Thailand has a capacity of 500 tonnes per year, and by 2025, the fiber had been adopted by more than 45 brands across 193 items. Burberry became the first luxury label to work with Spiber, releasing a scarf that incorporates 30 percent Brewed Protein fiber. Iris van Herpen debuted a bridal look made with the material at Paris Fashion Week AW25. Yuima Nakazato featured it in his AW 2024–2025 couture collection at Haute Couture Week in Paris. The collaboration between Spiber and A-POC Able Issey Miyake, designated the Type-XI Spiber project, produced a dress and bolero that develop their pleated structures through the material itself — weft yarns of Brewed Protein fiber combined with polyester, activated by differences in shrinkage during processing. No applied ornamentation, no interfacing, just the material doing what it was engineered to do. The dress retails at $2,595 and the bolero at $1,880, each in a single size, each functioning as much as a research object as a garment. “Some designs in this library resemble spider silk more closely, while others are closer to silkworm silk,” Spiber Executive Vice President Kenji Higashi said of the company’s growing portfolio of proprietary protein designs, which now includes amino acid sequences with no analog anywhere in nature.
Kraig Biocraft Laboratories, based in Lansing, Michigan, takes a more direct route: instead of replacing the silkworm, it rewires it. Working with CRISPR-Cas9 gene editing, which arrived in the early 2010s and “significantly improved the expression level of spider silk protein,” according to Chengliang Gong, a transgenic silkworm expert at Soochow University, Kraig has engineered worms with enough spider DNA to spin what the company describes as supersilk. The fiber doesn’t quite reach spider silk’s legendary physical benchmarks, but it clears conventional silk’s with notable room to spare. “This material is not gonna stop a 747,” Kraig Biocraft founder and CEO Kim Thompson told National Geographic, “but it’s better than regular silk. It’s stronger and more flexible.” Commercial-scale farms in Vietnam — where mulberry leaves are plentiful and sericulture expertise runs deep — are now producing the fiber in meaningful quantities, and sample fabric will ship to major clothing brands for testing in 2026. “After all these years,” Thompson said, “we are finally going to make the shipment.”
AMSilk, a German biotech that brews spider silk proteins using genetically engineered microbes, has found its near-term footing not in fashion but in household products. Its proteins form a microscopic, nontoxic biofilm that repels water, offering a bio-based alternative to the surfactants and synthetic compounds found in conventional detergents and dishwashing soaps. “Dishwashing soap is full of chemicals right now,” Gudrun Vogtentanz, AMSilk’s chief scientific officer, said. “If you take out the chemicals and add our spider silk protein instead, you get the same performance, but from a sustainability or an environmental point of view, it’s way better.” Sustainable dish soap may not be the silk revolution anyone imagined, but it keeps a research department running toward larger ambitions.
In Pittsburgh, Noah Snyder and his team at BioInterphase Materials are raising silkworms in a repurposed firehouse, studying sericulture as a potential path toward fiber composites reinforced with biological materials. The company has accumulated between $5 million and $10 million in government contracts with departments including energy and defense. “Our mission is to restore and reinforce life,” Snyder told the Pittsburgh Post-Gazette. “So we use bioengineering — which is really just the mixture between biology, chemistry and engineering — to solve things, either for biology or with biological materials.” His approach to the Army’s need for water- and oil-resistant fabrics without PFAS — the so-called forever chemicals resistant to heat, water, and stains — was characteristically direct. “We were developing water and oil proof materials using only biomaterials,” Snyder said. “So, things that we can get from nature. Borrowing from nature. Formulating it into a material, and solving a problem.”
That same openness extends to the silkworm project itself. “If you take the mentality of ‘oh, you probably couldn’t do this,’ then you would never take that first step,” Snyder said. “And so even if this [silkworm] project, this concept, doesn’t go anywhere, we’ll have learned a lot more. And I don’t think our organization is ever in a bad place where the only thing we get is learning. We plant all these seeds with these ideas that seem crazy, nurture the ones that kind of seem to be working, and then find the right partners to go commercialize so that we can do what we’re best at — which is living in this crazy, kooky creative-engineering world.”
The ethics question traditional silk has always avoided
For all of fashion’s recent transparency around supply chains, conventional silk’s animal welfare problem remains surprisingly underreported. Fur drives protests and column inches; silk slips by largely unexamined. Yet the scale is considerable. Silkworms are moths — domesticated so completely over millennia that the Bombyx mori species often emerges from its cocoon blind and with underdeveloped wings, the result of centuries of selective breeding for silk yield rather than survival.
On a conventional farm, the cocoon is dropped into boiling water while the worm is still inside, loosening the adhesive that binds the fiber and allowing a single continuous thread — sometimes nearly a mile long — to be unspooled. Whether silkworms experience pain the way mammals do is contested: a study published in the journal Science Advances found that fruit flies can experience chronic, long-lasting pain, while research from the University of Cambridge published in The Canadian Entomologist suggests the likelihood in insects is low. Neither study addresses silkworms specifically, and science has not ruled the possibility out entirely. The Higg Materials Sustainability Index further complicates silk’s pristine image by ranking it as the most environmentally unfriendly fabric, largely due to its global warming potential, intensive land use for mulberry cultivation, and fossil fuel consumption in processing.
Peace silk, also called ahimsa silk — from the Sanskrit word for non-violence — attempts an answer, allowing silkworms to complete their metamorphosis before their cocoons are collected. Developed in 1990 by Indian government officer Kusuma Rajaiah, the process adds about ten days to production and results in a textured, spun fiber rather than the continuous filament of conventional silk. It is more labor-intensive and more expensive. It also carries complications of its own: an investigation by Beauty Without Cruelty India found that in at least one facility, female moths were crushed after laying eggs and male moths were repeatedly used for mating before being discarded. Peace silk is a meaningful step toward a more thoughtful production model, but it does not fully resolve the ethical math.
The more genuinely animal-free route is the biotech fiber. Bolt Threads, the California-based biotech company, developed Microsilk by engineering yeast to express spider silk proteins through fermentation with sugar and water before pivoting away from textiles to focus on beauty and personal care, where it now markets its silk proteins as b-silk and xl-silk. Even the most compelling innovations must eventually face commercial reality — a lesson that has shaped how every company in this space calibrates its ambitions. “The goal is to mimic, and eventually surpass, the performance of natural spider silk, and then push it toward real-world applications,” said Wenbo Hu, a spider silk expert at Southwest University in central China. “We’re getting incredibly close.”
The applications researchers are most excited about are not scarves or blouses. Xingmei Qi, who researches spider silk-based therapeutics at Soochow University, is working on a new generation of vaccines in which spidroin nanocapsules would carry immune-stimulating molecules to their targets and release them at slow, sustained rates. Spidroin-derived coatings can line catheters and surgical meshes to reduce infection and blood clotting. “Beyond fabric, recombinant spider silk proteins can be processed into diverse forms—films, hydrogels, sponges, microcapsules, and nanoparticles,” Qi said. “What once seemed nearly impossible is now becoming technically and economically feasible.” The proteins’ physical makeup makes them exceptionally well-suited to the body. “Spidroin nanoparticles already meet most of the critical biomedical requirements,” Qi said. “They are biodegradable, biocompatible, safe, and can be produced under mild, scalable conditions.” The design ambitions extend further still. “With the advancement of synthetic biology and protein-engineering technologies, it is entirely possible to design artificial proteins that outperform natural spider silk,” said Gong.
“Ultimately, we hope that these silk-inspired materials will bridge biology and medicine,” Qi said, “turning one of nature’s most remarkable structural proteins into a platform for human health.”
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