Spider silk is also known as gossamer. It is a sought-after biomaterial. Spider silk is a protein fiber made in the glands of a spider. This silk is flexible and lightweight. These fibers are waterproof and have a tensile strength similar to that of steel. These fibers can be stretched up to 40% of their original length without breaking.
Scientists across the globe have been trying to mimic the properties of spider silk into synthetic silk fibers, as spiders cannot be farmed; they are territorial and cannibalistic in close proximity. Over the last few years, scientists have developed multiple ways to synthesize the properties of spider silk using genetically modifying Escherichia coli bacteria, plants, silkworms, yeasts, and even goats. Some of these methods are not scalable to the commercial production; however, methods such as fermentation of yeast are being used by companies, such as Bolt Thread, for commercial production of synthetic silk fibers. These fibers are used in applications such as textiles, defense, and health care.
These companies have developed industrial-scale processes to ferment synthetic spider silk in bacteria. The result is a growing industry of sustainably sourced and environmentally friendly material that can supplant other raw materials limited by finite availability. The other aspect of spider silk is that it holds the promise of delivering impressive new functionalities and features for different types of applications.
Spider silk is an example of a material that could be disruptive in many applications. Stronger than steel, tougher than Kevlar but also flexible, the range of applications is large. They are lightweight and virtually invisible to the human immune system, giving them “revolutionary potential” for medicine and the industry.
Among the newer applications of spider silk being considered are microphones in hearing aids and cell phones. The German company AMSilk has entered into an agreement with Airbus to develop structural materials for aircraft using synthetic spider silk. A biodegradable shoe has been developed by Adidas using this material. Silk has high-value applications in cosmetics, and Givaudan has acquired the cosmetics business of AMSilk.
Most companies to date are only now getting a grasp of how to reliably make spider silk through batch fermentation without any enhanced features or functionality. An individual spider can make up to eight different silks that all have distinct uses, many of which scientists are still seeking to characterize. To successfully implement silk into any system, researchers need an in-detail quantitative, correlative, and causal understanding of the interplay of the different sequence motives and scales, which govern the tuning of the tensile properties. So far, only limited information on selected silks from a small number of spider species is available.
Scientists at the Air Force Research Lab and Purdue University have been examining natural silk to get a sense of its ability to regulate temperature – silk can drop 10 to 15 degrees Fahrenheit through passive radiative cooling, which means radiating more heat than it absorbs, according to an Air Force news release.
Those researchers want to apply that property to synthetics, like artificial spider silk, which is stronger than Kevlar, the polymer typically used in body armor, and more flexible than nylon.
Enhancing body armor and adding comfort for troops is one of many improvements hoped for by a team led by Dr. Augustine Urbas, a researcher in the Functional Materials Division of the Materials and Manufacturing Directorate.”Understanding natural silk will enable us to engineer multifunctional fibers with exponential possibilities. The ultra-strong fibers outperform the mechanical characteristics of many synthetic materials as well as steel,” Urbas said in the release. “These materials could be the future in comfort and strength in body armor and parachute material for the warfighter.”
In addition to making flexible, cooler body armor, the material could also be used to make tents that keep occupants cooler as well as parachutes that can carry heavier loads. Artificial spider silk may initially cost double what Kevlar does, but its light weight, strength, flexibility, and potential for other uses make it more appealing, according to the release. Air Force researchers are also looking at Fibroin, a silk protein produced by silkworms, to create materials that can reflect, absorb, focus, or split light under different circumstances.
US Army to test body armor made from spider silk
In 2018, Kraig Biocraft Laboratories announced that it has delivered ballistic panels made of spider silk to the U.S. Army for testing as body armor. The panels, constructed out of the companies proprietary Dragon Silk, will be evaluated for their ability to stop bullets and other ballistic threats like shrapnel.
Dragon Silk is a genetically engineered material, which is produced by silkworms but can mimic the strength and flexibility of spider silk. Kraig Biocraft claims that the genetically modified worms can be included in the infrastructure used by the standard silk industry.
Spider silk is extraordinarily strong and is theorized to provide ballistic protection with much less weight and better flexibility than conventional armor like Kevlar. The silk will be produced at the company’s facility in Indiana. Spider silk has long been known to have superior strength, flexibility and ballistic protection, but raising spider colonies for production proved to be impossible, since the spiders would often eat each other. Genetically engineered silkworms are more practical and allow for much greater production of the material, Kraig Biocraft said.
Layered weave spider silk is much stronger than steel. The company says that is has patented a large number of genetic proteins which were then implanted in domestic silkworms for body armor production. The material has special implications for ballistic underwear, providing protection for the groin region, which has proven difficult to protect. Previous efforts, such as Vietnam-era Kevlar shorts, and modern alternatives such as dangling Kevlar flaps have proven to be cumbersome and unpopular.
Office of Naval Research (ONR) Global
The Office of Naval Research (ONR) Global, in partnership with the Air Force Office of Scientific Research (AFOSR), is sponsoring the revolutionary work of Dr. Thomas Scheibel, professor for biomaterials and head of the Biomaterials Department at the University of Bayreuth, Germany. This project aims to further understand the spider dragline silks’ structure-function relationship by investigating its different hierarchical levels comprehensively and in depth, using both a correlative as well as a design approach.
Dragline silk, also called major ampullate silk, of eight to 10 closely related spider species will be selected for the investigation of their primary, secondary and quaternary structure, using a wide array of techniques: RNA sequencing, synchrotron-based X-ray scattering, nuclear magnetic resonance (NMR), thermal analysis, electron and force microscopy, and static and dynamic tensile testing. The influence of the investigated structures and their interdependence on silk tensile properties will be analyzed with a regression model. This project will be the first to obtain data of sufficient resolution to develop a predictive model, which can estimate the impact of changes in elementary building blocks on the molecular level on tensile properties at the macroscopic scale.
In parallel, a husbandry regime of select spider species will facilitate the manipulation of specific silk and silk-related sequences to deduce their role in silk functionality. Predictions based on regression analysis will be used to test the limits of silk tuning, and novel functionalities can be produced by inserting non-native sequence elements. This newly created model spider system is not limited to fundamental silk research — it will find wide applicability in the study of spider biology.
Scheibel stated, “If we are successful, we can create a model system in which frame-shift mutations, point mutations, in-frame deletions and insertions can be produced in silk and silk related genes to facilitate the investigation of the spider silk´s structure function relationship.”
Silk Spun by Graphene-Fed Spiders Is One of the Strongest Materials on Earth
In a new study published in 2D Materials, Nicola Pugno at the University of Trento in Italy and his team detail how they cranked arachnids’ already impressive metabolic process up to 11 by adding graphene and carbon nanotubes to a spider’s drinking water.
One of the goals of Synthetic Biology that is the creation of bioengineered microorganisms (and possibly other life forms) that can produce pharmaceuticals, detect toxic chemicals, break down pollutants, repair defective genes, destroy cancer cells, and generate hydrogen for the post petroleum economy.
Scientists from Italy have found a way to increase the overall strength and durability of spider silk. After feeding a spider a small amount of graphene and carbon nanotubes, the creature produced webs that were five times stronger than normal.
Graphene the world’s first 2D nanomaterial, is widely regarded as the “wonder material” of the 21st century due to the combination of its extraordinary properties. As a single layer of graphite, it is the thinnest material (monoatom thick), transparent, 200 times stronger than steel, yet as flexible as rubber, more conductive than copper, excellent thermal conductor and impermeable to moisture and gases. It is fire resistant yet retains heat.
Pugno believes it could eventually be applied to creatures beyond spiders. “This process of the natural integration of reinforcements in biological structural materials could also be applied to other animals and plants, leading to a new class of ‘bionicomposites’ for innovative applications,” he asserted.
And similar research has been done with graphene in other creatures. In 2016, a team of scientists fed silkworms carbon nanotubes and graphene, and found that they were able to spin an ultra-strong ‘super-silk.’
Researchers at Tsinghua University found that feeding the larvae a diet fortified with nanomaterials, including graphene and carbon nanotubes, enabled the larvae to reinforce the threads themselves. Parts of the nanomaterials were incorporated into the fibres spun by the insects. According to Scientific American, the reinforced silk is far stronger and able to withstand 50 per cent more stress before the strands break.
They found that the materials were then incorporated into the spider’s silk, which produced webbing five times stronger than normal putting it on par with the likes of pure carbon fibers and Kevlar — the strongest materials on Earth.
“We already know that there are biominerals present in the protein matrices and hard tissues of insects, which gives them high strength and hardness in their jaws, mandibles, and teeth, for example,” said. “So our study looked at whether spider silk’s properties could be ‘enhanced’ by artificially incorporating various different nanomaterials into the silk’s biological protein structures.”
So far what has been produced has only been tested on a small scale to look at the concept, but Dr Pugno said the results are promising. ‘It is among the best spun polymer fibers in terms of tensile strength, ultimate strain, and especially toughness,’ she explained.
In 2015, A team of researchers working in Italy has found that simply spraying a spider with a carbon nanotube solution can cause the spider to spin stronger webs
“Here, we report the production of silk incorporating graphene and carbon nanotubes directly by spider spinning, after spraying spiders with the corresponding aqueous dispersions. We observe a significant increment of the mechanical properties with respect to the pristine silk, in terms of fracture strength, Young’s and toughness moduli. We measure a fracture strength up to 5.4 GPa, a Young’s modulus up to 47.8 GPa and a toughness modulus up to 2.1 GPa, or 1567 J/g, which, to the best of our knowledge, is the highest reported to date, even when compared to the current toughest knotted fibres. This approach could be extended to other animals and plants and could lead to a new class of bionic materials for ultimate applications.”
Synthetic Spider Silk Market
The global Synthetic Spider Silk market size is projected to reach USD 19840 million by 2026, from USD 7865.6 million in 2020, at a CAGR of 16.7% during 2021-2026.
Key Drivers and Restraints of Global Synthetic Spider Silk Market
The synthetic spider silk market has developed significantly of late. This can be primarily ascribed to the rise in demand for synthetic spider silk in defense applications and their extensive usage in health care applications. This is prompting companies to increase the production of synthetic spider silk. Additionally, easy availability of raw materials to manufacture synthetic spider silk is anticipated to boost the market during the forecast period.
Technological advancements in the global synthetic spider silk market are increasing. Companies are striving to develop new and better methods to manufacture these fibers. Development of new manufacturing processes for synthetic spider silk and rise in utilization of these fibers are expected to propel the global synthetic spider silk market during the forecast period.
Synthetic Spider Silk: Product Segment
In terms of product, the global synthetic spider silk market can be segmented into genetically modified yeast fermentation, genetically modified silkworm, genetically modified Escherichia coli bacteria fermentation, and others
The genetically modified yeast fermentation segment is anticipated to account for significant share of the global synthetic spider silk market during the forecast period due to extensive usage of synthetic spider silk in applications such as textiles and health care across the globe
Synthetic Spider Silk: Application Segment
In terms of application, the global synthetic spider silk market can be divided into textile, automotive, defense, health care, and others
The textile segment is estimated to expand at a rapid pace during the forecast period due to the extensive usage of synthetic spider silk in the manufacture of sports apparel
North America to Dominate Synthetic Spider Silk Market
In terms of region, the global synthetic spider silk market can be divided into North America, Europe, Asia Pacific, Latin America, and Middle East & Africa North America dominated the synthetic spider silk market in 2020. This trend is anticipated to continue during the forecast period owing to the rise in demand for synthetic spider silk fibers in defense applications. The synthetic spider silk market in Europe is anticipated to expand at a rapid pace owing to the increase in demand for these fibers in health care applications in the region.
Key Manufacturers Operating in Global Synthetic Spider Silk Market
The global synthetic spider silk market was consolidated in 2020. Major players have prominent presence in developed and developing countries. Key manufacturers operating in the global synthetic spider silk market include:
Kraig Biocraft Laboratories, Inc.
Bolt Threads Inc.
Polartec, the premium provider of innovative and sustainable textile solutions, and Kraig Biocraft Laboratories (Kraig) (OTC:KBLB), the biotechnology company focused on the development and commercialization of spider silk, announce plans to bring to market the first fabrics made from spider silk. Initially developed for specialized military applications, these first-of-their-kind materials made from recombinant spider silk will eventually service the global market for high performance textiles and apparel.
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