Scientists use spider silk to make clothing and medical equipment

The touting of spider silk began in the 1810s. At the time, Franois Xavier Bon de Saint Hilaire, president of the Royal Society of French Sciences in Montpellier, wrote in a letter to his colleague: "You will be very surprised to hear that the silk produced by the spider is as beautiful, strong and smooth as ordinary silk . The modern touting claims that spider silk is five times stronger than steel, but still more flexible than rubber. If it can be made into a rope, then a large-scale net will be able to cover a jetliner. The key word is "if". The researchers first cloned the spider silk gene in 1990 with a view to implanting it into other organisms to produce silk. Spiders cannot be cultured like silkworms because they are territorial and will be homogeneous. Today, E. coli, yeast, plants, silkworms and even goats can produce a large number of spider silk proteins through genetic modification, although these proteins are usually shorter and simpler than the spider's own proteins. The company has successfully transferred these proteins into lines of high enough to produce some garment prototypes, including Adidas running Shoes and North Face's lightweight coats. However, to date, the company is still working on mass production of such garments. Some managers say they may eventually change their strategy. Bolt Threads, a startup based in Emeryville, Calif., says it has perfected the method of growing spider silk proteins in yeast and is expected to produce tons of spider silk per year. In Lansing, Michigan, Kraig Biocraft Labs said that it only needs to negotiate with Vietnam's sericulture field to create a large mixture of spider silk and silk. Currently, the US military is testing it for ballistics protection. “Since the 1990s, great progress has been made in this area. At the time, large-scale production of spider silk seemed to be out of reach, both in terms of functional scale and commercial scale.” Royal Institute of Technology, Sweden Home My Hedhammar said. However, many biotech and research observers are cautious about the prospect of mass production of spider silk ropes and fibers. “Currently, the field has not progressed to this point.” Cheryl Hayashi, a spider silk geneticist at the American Museum of Natural History, said, “We still can’t see these things on the shelves of the store.” People’s dreams are to imitate the spit The strongest of the seven kinds of silk: a spider's silk that allows the spider to hang on the net and contains seven spider silk proteins. These protein molecules are large – each with a maximum of 600 kilodaltons (kDa), which is almost twice the size of a normal human protein. This makes it difficult to produce in genetically modified organisms. Most companies choose to produce versions from 50 to 200 kDa because they are easier to express. The silk produced by these smaller proteins is usually not as strong and flexible. "In one way, as the protein gets smaller, the mechanical properties are lost," said Randy Lewis, a chemist at Utah State University. The Lewis team first cloned the spider silk gene. At the same time, studies have confirmed that mimicking the way spiders spin a concentrated protein solution into fibers is also difficult. Currently, Lewis is able to spin spider silk proteins into water-insoluble fibers and eliminates the need for expensive and potentially toxic organic solvents. The team led by Daniel Sderberg, a fluid physicist at the Royal Institute of Technology in Sweden, found a way to use linear cellulose fibers in wood and paper to line up spider silk proteins to form fibers. However, spinning these filaments into fibers on a commercial scale is another matter. “Magnifying scale is a huge challenge,” said Lin Rmer, chief technology officer at AMSilk, a spider silk startup in Munich, Germany. Spider silk proteins are on the market, but only in the field of cosmetics and medical devices, not in high-strength fibers. AMSilk grows spider silk protein in E. coli and drys the purified protein to form a powder, or mixes it into a gel for use as an additive to personal care products such as moisturizing lotions. Spider silk protein is said to help the lotion form a very smooth, breathable protective layer on the skin. Rmer said that the company currently sells several tons of purified spider silk protein components every year. AMSilk is also completing a clinical trial of silicone breast implants wrapped with the company's spider silk protein. Since these proteins contain highly repetitive small amino acid sequences, they are said to be hardly recognized by the immune system. This kind of package can also get rid of bacteria more easily than Teflon or stainless steel. Rmer said these advantages should allow companies to use spider silk to improve many implants from the artificial hip to the catheter. Kraig Biocraft Labs and Spiber Technologies in Stockholm say they are also developing similar applications.