Category Archives: clothing

Clothes that can help combat rising temperatures

This October 9, 2024 news item on ScienceDaily floats an idea that’s a big improvement over letting a bag of ice cubes melt on your body so you can cool down,

A team of international researchers has developed a natural fabric that urban residents could wear to counter rising temperatures in cities worldwide, caused by buildings, asphalt, and concrete.

As heatwaves become more prominent, cooling textiles that can be incorporated into clothes, hats, shoes and even building surfaces provide a glimpse into a future where greenhouse gas-emitting air conditioners may no longer be needed in our cities.

An October 10, 2024 University of South Australia (UNISA) press release (also on Eurekalert but published October 9, 2024), which originated the news item, offers more information about the cooling textiles, Note: Links have been removed,

Engineers from Zhengzhou University and the University of South Australia say the wearable fabric is designed to reflect sunlight and allow heat to escape, while blocking the sun’s rays and lowering the temperature. They have described the textiles in the latest issue of Science Bulletin.

The fabric promises to bring relief to millions of city dwellers experiencing warmer and more uncomfortable temperatures caused by global climate change and fewer green spaces.

UniSA visiting researcher Yangzhe Hou says the fabric leverages the principle of radiative cooling, a natural process where materials emit heat into the atmosphere, and ultimately into space.

“Unlike conventional fabrics that retain heat, these textiles are made of three layers that are engineered to optimise cooling,” Hou says.

The upper layer, made of polymethyl pentene fibres, allows heat to radiate effectively. The middle layer, composed of silver nanowires, enhances the fabric’s reflectivity, preventing additional heat from reaching the body. The bottom layer, made of wool, directs heat away from the skin, ensuring that wearers remain cool, even in the hottest urban environments.

“In our experiment, when placed vertically, the fabric was found to be 2.3°C cooler than traditional textiles, and up to 6.2°C cooler than the surrounding environment when used as a horizontal surface covering.

“The fabric’s ability to passively reduce temperatures offers a sustainable alternative to conventional air conditioning, providing energy savings and reducing the strain on power grids during heatwaves.”

Zhengzhou University researchers Jingna Zhang and Professor Xianhu Liu say the technology not only addresses the immediate problem of urban heat islands, but also contributes to broader efforts to mitigate climate change and move towards more sustainable urban living.

It is hoped the technology could be adapted for even broader applications, including construction material, outdoor furniture and urban planning.

While the fabric holds significant promise, researchers say the current production process is costly, and the long-term durability of the textiles needs further investigation and government support before it can be commercialised.

“Whether consumers are willing to pay more for wearable fabrics depend on the cooling effect, durability, comfort and their environmental awareness,” the researchers say.

Here’s a link to and a citation for the paper,

Radiation cooling textiles countering urban heat islands by Xianhu Liu, Jingna Zhang, Yangzhe Hou, Chuntai Liu, Changyu Shen. Science Bulletin Volume 69, Issue 21, 15 November 2024, Pages 3318-3320 DOI: https://doi.org/10.1016/j.scib.2024.09.008 Available online 12 September 2024, Version of Record 5 November 2024

This paper is behind a paywall.

Prototype of nanofibre uniforms for Australian military

CSIRO project lead Dr Yen Truong (L) and Head of Program Management at DMTC, Deepak Ganga (R) with the prototype uniform. Courtesy: CSIRO

I last had a story about the Australian military and advanced technology in a June 18, 2023 posting titled, “Mind-controlled robots based on graphene: an Australian research story” where soldiers were patrolling with mind-controlled robotic dogs.

This story is textile-oriented (h/t Azonano’s September 24, 2024 news item). A September 24, 2024 Commonwealth Scientific and Industrial Research Organisation (CSIRO) press release announces a new kind of uniform,

Researchers at Australia’s national science agency, CSIRO, have successfully developed a next-generation uniform prototype that employs nanofibres to safeguard Australian troops from chemical and biological threats.

The innovative material is a lightweight fabric that effectively filters out harmful particles while remaining light-weight and breathable, keeping the wearer comfortable in extreme temperatures.

CSIRO Manufacturing Research Unit Director, Dr Marcus Zipper said this textile innovation was the result of collaboration with industry and research partners, including DMTC.

“Our nanofibre technology, pioneered by CSIRO scientists, has the potential to significantly improve the level of protection soldiers’ uniforms provide and can also be used for non-military applications, including protecting emergency responders and hazmat crews,” Dr Zipper said.

“CSIRO research and development in materials science looks to improve how a particular material functions – we work across a broad range of advanced materials including metals, composites, polymers, adsorbents and nanofibres,” Dr Zipper said.

The initial phase of this project was funded by the Department of Defence. The successful nanofibre suit prototype was coordinated by DMTC Limited.

Also involved in supporting the project are Bruck Textiles, Defence Science and Technology Group and RMIT University.

Head of Program Management at DMTC, Deepak Ganga, said the new prototype uniform could deliver a significant leap forward in soldier protection, ensuring better comfort and mobility in harsh environments.

“This project demonstrates the power of collaboration. CSIRO’s scientific excellence in nanofibre research has been matched with the expertise of our partners in textiles, defence science, and manufacturing,” Mr Ganga said.

“This has resulted in a groundbreaking solution that offers benefits for Australian troops, for the first responder community and, potentially for Australia’s alliance partners,” he said.

CSIRO project lead Dr Yen Truong said key to the prototype’s success lies in its innovative nanofibre technology, developed by CSIRO scientists.

“We harnessed the unique properties of nanofibres to create a lightweight fabric that effectively filters out harmful particles while remaining highly breathable,” said Dr Truong.

“In rigorous testing, the prototype surpassed all performance targets for air filtration, air permeability, thermal comfort, and chemical protection.

“This means it effectively filters pollutants from the air, allows for breathability, maintains comfortable temperatures even in extreme conditions, and offers superior protection from hazardous chemicals.”

With DMTC Limited, Dr Truong and team are seeking funding to progress to the next stage of development, which is expected to involve field testing with Australian Defence Force personnel and further refinement of scaled manufacturing processes with industrial partners.

As you can see, they’re being quite close-lipped about how or from what the textile is constituted. This September 24, 2024 CSIRO article by Rebecca Willetts offers a little more information,

For soldiers on the frontline, chemical and biological hazards are a sobering threat.

Traditional bulky protective suits offer a crucial layer of protection but come at the expense of breathability and mobility. This can lead to discomfort, heat stress and even hinder performance in harsh environments – potentially jeopardising the wearer’s health.

Our researchers are working to revolutionise personal protective equipment. We’ve developed a next-generation suit prototype that prioritises safety and comfort for soldiers and first responders.  

The secret to our breakthrough lies in nanofibres – incredibly fine filaments at least 100 times thinner than a human hair. These tiny wonders have an extraordinary surface area that prevents harmful aerosol particles from passing through. What truly sets them apart is their breathability. Unlike traditional protective materials, nanofibre layers allow air to circulate freely – ensuring the wearer remains comfortable even in extreme conditions.

Senior researcher Dr Yen Truong is leading the project at CSIRO. She explains that nanofibres have the potential to revolutionise the way we think about protective gear. 

“They offer a unique combination of filtration performance while maintaining breathability. The latter represents a challenge that has long hampered the development of effective lower thermal burden protective suits,” she says. 

The Nano Protective Adsorbent Composite (NPAC) project, which was made possible with Federal Government support, began in 2017. 

Our team of scientists at CSIRO worked hand-in-hand with experts from Bruck Textiles, the Defence Science and Technology Group and RMIT University under the coordination of DMTC. This collaboration brought together knowledge and experience in nanotechnology, textile manufacturing, defence science and fashion design. 

The first success was the development of the innovative nanofibre-based fabric. This fabric acts as a barrier against harmful airborne particles while maintaining airflow. Scaling up this technology from the laboratory to commercial production presented a significant challenge.

“It’s easy enough to create a composite nanofibre material in a small lab setting, but transitioning to mass production is a different thing altogether,” Yen says. 

Our pilot-scale electrospinning machine produces the nanofibre. This larger-than-typical lab equipment played a crucial role in the production of larger quantities of fabric.

This demonstrated the technology’s potential for commercialisation, paving the way for real-world applications. A major breakthrough came in 2023 when Bruck Textiles, a leading Australian textile manufacturer, successfully produced 90 metres of the fabric. This material was then fabricated into a prototype uniform, which underwent rigorous testing. 

In testing it surpassed performance targets for air filtration, air permeability, thermal comfort, and chemical protection. This meant the suit not only protected the wearer from hazardous substances, but also offered comfort and mobility in demanding situations.

“We envision a future where firefighters, paramedics and other frontline workers can focus on their critical tasks without being hindered by heavy, cumbersome protective gear,” Yen says.

It’s a long way from 90 meters of fabric to producing the quantities required to outfit military and other personnel. I wish them good luck!

As for more details about the nanofibers, I wasn’t able to find much about them in a relatively short online search but i did find more about Dr. Truong’s work here on her ResearchGate profile page.

First-of-its-kind thermally-insulated and breathable soft robotic clothing for use in extreme heat

An August 15, 2024 news item on ScienceDaily announces research that may help make people safer in extreme heat,

As global warming intensifies, people increasingly suffer from extreme heat. For those working in a high-temperature environment indoors or outdoors, keeping thermally comfortable becomes particularly crucial. A team led by Dr Dahua SHOU, Limin Endowed Young Scholar in Advanced Textiles Technologies and Associate Professor of the School of Fashion and Textiles of The Hong Kong Polytechnic University (PolyU) has developed first-of-its-kind thermally-insulated and breathable soft robotic clothing that can automatically adapt to changing ambient temperatures, thereby helping to ensure worker safety in hot environments. Their research findings have been published in the international interdisciplinary journal Advanced Science.

An August 14, 2024 Hong Kong Polytechnic University press release (also on EurekAlert but published on August 15, 2024), which originated the news item, elaborates on the issue and on the proposed solution,

Maintaining a constant body temperature is one of the most critical requirements for living and working. High-temperature environments elevate energy consumption, leading to increased heat stress, thus exacerbating chronic conditions such as cardiovascular disease, diabetes, mental health issues and asthma, while also increasing the risk of infectious disease transmission. According to the World Health Organisation, globally, there were approximately 489,000 heat-related deaths annually between 2000 and 2019, with 45% occurring in Asia and 36% in Europe.

Thermal protective clothing is essential to safeguard individuals in extreme high-temperature environments, such as firefighters who need to be present at fires [sic] scenes and construction workers who work outdoors for extended periods. However, traditional gear has been limited by statically fixed thermal resistance, which can lead to overheating and discomfort in moderate conditions, while its heat insulation may not offer sufficient protection in extreme fire events and other high-temperature environments. To address this issue, Dr Shou and his team have developed intelligent soft robotic clothing for automatic temperature adaptation and thermal insulation in hot environments, offering superior personal protection and thermal comfort across a range of temperatures.

Their research was inspired by biomimicry in nature, like the adaptive thermal regulation mechanism in pigeons, which is mainly based on structural changes. Pigeons use their feathers to trap a layer of air surrounding their skin to reduce heat loss to the environment. When the temperature drops, they fluff up their feathers to trap a significant amount of still air, thereby increasing thermal resistance and retaining warmth.

The protective clothing developed by the team uses soft robotic textile for dynamic adaptive thermal management. Soft actuators, designed like a human network-patterned exoskeleton and encapsulating a non-toxic, non-flammable, low-boiling-point fluid, were strategically embedded within the clothing. This thermo-stimulated system turns the fluid from a liquid into a gas when the ambient temperature rises, causing expansion of soft actuators and thickening the textile matrix, thereby enhancing the gap of still air and doubling the thermal resistance from 0.23 to 0.48 Km²/W. The protective clothing can also keep the inner surface temperatures at least 10°C cooler than conventional heat-resistant clothing, even when the outer surface reaches 120°C.

This unique soft robotic textile, made by thermoplastic polyurethane, is soft, resilient and durable. Notably, it is far more skin-friendly and conformable than temperature-responsive clothing embedded with shape-memory alloys and is adjustable for a wide range of protective clothing. The soft actuators have exhibited no signs of leakage after undergoing rigorous standard washing tests. The porous, spaced knitting structure of the material can also significantly reduce convective heat transfer while maintaining high moisture breathability. Not relying on thermoelectric chips or circulatory liquid cooling systems for cooling or heat conduction, the light-weighted, soft robotic clothing can effectively regulate temperature itself without any energy consumption.

Dr Shou said, “Wearing heavy firefighting gear can feel extremely stifling. When firefighters exit a fire scene and remove their gear, they are sometimes drained nearly a pound of sweat from their boots [sic]. This has motivated me to develop a novel suit capable of adapting to various environmental temperatures while maintaining excellent breathability. Our soft robotic clothing can seamlessly adapt to different seasons and climates, multiple working and living conditions, and transitions between indoor and outdoor environments to help users experience constant thermal comfort under intense heat.”

Looking forward, Dr Shou finds the innovation to have a wide range of potential applications, from activewear, winter jackets, healthcare apparel and outdoor gear, to sustainable textile-based insulation for construction and buildings, contributing to energy-saving efforts. Supported by the Innovation and Technology Commission and the Hong Kong Research Institute of Textiles and Apparel, Dr Shou and his team have also extended the thermo-adaptive concept to develop inflatable, breathable jackets and warm clothing. This soft robotic clothing is suitable for low-temperature environments or sudden temperature drops to aid those who are stranded in the wilderness to maintain normal body temperature.

Here’s a link to and a citation for the paper,

Soft Robotic Textiles for Adaptive Personal Thermal Management by Xiaohui Zhang, Zhaokun Wang, Guanghan Huang, Xujiang Chao, Lin Ye, Jintu Fan, Dahua Shou. Volume 11, Issue 21 June 5, 2024 2309605 First published online: 26 March 2024 DOI: https://doi.org/10.1002/advs.202309605

This paper is open access.

Converting body heat into electricity with smart fabric

This bioenergy harvesting story is from the University of Waterloo (Ontario, Canada), where its researchers were part of an international collaboration. From an August 14, 2023 news item on ScienceDaily,

Imagine a coat that captures solar energy to keep you cozy on a chilly winter walk, or a shirt that can monitor your heart rate and temperature.Picture clothing athletes can wear to track their performance without the need for bulky battery packs.

University of Waterloo researchers have developed a smart fabric with these remarkable capabilities.

The fabric has the potential for energy harvesting, health monitoring, and movement tracking applications.

An August 14, 2024 University of Waterloo news release (also on EurekAlert), which originated the news item, provides more information about the new fabric and the research team, Note: A link has been removed,

The new fabric developed by a Waterloo research team can convert body heat and solar energy into electricity, potentially enabling continuous operation with no need for an external power source. Different sensors monitoring temperature, stress, and more can be integrated into the material.

It can detect temperature changes and a range of other sensors to monitor pressure, chemical composition, and more. One promising application is smart face masks that can track breath temperature and rate and detect chemicals in breath to help identify viruses, lung cancer, and other conditions.

“We have developed a fabric material with multifunctional sensing capabilities and self-powering potential,” said Yuning Li, a professor in the Department of Chemical Engineering. “This innovation brings us closer to practical applications for smart fabrics.”

Unlike current wearable devices that often depend on external power sources or frequent recharging, this breakthrough research has created a novel fabric which is more stable, durable, and cost-effective than other fabrics on the market. 

This research, conducted in collaboration with Professor Chaoxia Wang and PhD student Jun Peng from the College of Textile Science and Engineering at Jiangnan University, showcases the potential of integrating advanced materials such as MXene and conductive polymers with cutting-edge textile technologies to advance smart fabrics for wearable technology.

Li, director of Waterloo’s Printable Electronic Materials Lab, highlighted the significance of this advancement, which is the latest in the university’s suite of technologies disrupting health boundaries.

“AI technology is evolving rapidly, offering sophisticated signal analysis for health monitoring, food and pharmaceutical storage, environmental monitoring, and more. However, this progress relies on extensive data collection, which conventional sensors, often bulky, heavy, and costly, cannot meet,” Li said. “Printed sensors, including those embedded in smart fabrics, are ideal for continuous data collection and monitoring. This new smart fabric is a step forward in making these applications practical.”

The next phase of research will focus on further enhancing the fabric’s performance and integrating it with electronic components in collaboration with electrical and computer engineers. Future developments may include a smartphone app to track and transmit data from the fabric to healthcare professionals, enabling real-time, non-invasive health monitoring and everyday use.

Here’s a link to and a citation for the paper,

MXene-based thermoelectric fabric integrated with temperature and strain sensing for health monitoring by Jun Peng, Fangqing Ge, Weiyi Han, Tao Wu, Jinglei Tang, Yuning Li, Chaoxia Wang. Journal of Materials Science & Technology Volume 212, 20 March 2025, Pages 272-280

This paper is behind a paywall but you will be able to read snippets in a preview.

Designers make dissolvable textiles from gelatin

Am I the only one wondering what happens if your textiles start dissolving early? This excerpt from a June 17, 2024 news item on ScienceDaily announcing the research does not address my quandary,

Introducing the fashion of the future: A T-shirt that you can wear a few times, then, when you get bored with it, dissolve and recycle to make a new shirt.

Researchers at the ATLAS Institute at the University of Colorado Boulder are now one step closer to that goal. In a new study, the team of engineers and designers developed a DIY machine that spins textile fibers made of materials like sustainably sourced gelatin. The group’s “biofibers” feel a bit like flax fiber and dissolve in hot water in minutes to an hour.

The quandary is addressed in a manner of speaking in a June 17, 2024 University of Colorado at Boulder news release (also on EurekAlert) by Daniel Strain, which originated the news item, that also gives more context for the research and explains what the researchers are hoping to achieve, Note: A link has been removed,

“When you don’t want these textiles anymore, you can dissolve them and recycle the gelatin to make more fibers,” said Michael Rivera, a co-author of the new research and assistant professor in the ATLAS Institute and Department of Computer Science.

The study tackles a growing problem around the world: In 2018 alone, people in the United States added more than 11 million tons of textiles to landfills, according to the Environmental Protection Agency—nearly 8% of all municipal solid waste produced that year. 

The researchers envision a different path for fashion.

Their machine is small enough to fit on a desk and cost just $560 to build. Lázaro Vásquez [Eldy Lázaro Vásquez, doctoral student in the ATLAS Institute,] hopes the device will help designers around the world experiment with making their own biofibers.

“You could customize fibers with the strength and elasticity you want, the color you want,” she said. “With this kind of prototyping machine, anyone can make fibers. You don’t need the big machines that are only in university chemistry departments.”

Spinning threads

The study arrives as fashionistas, roboticists and more are embracing a trend known as “smart textiles.” Levi’s Trucker Jacket with Jacquard by Google, for example, looks like a denim coat but includes sensors that can connect to your smartphone. 

But such clothing of the future comes with a downside, Rivera said:

“That jacket isn’t really recyclable. It’s difficult to separate the denim from the copper yarns and the electronics.”

To imagine a new way of making clothes, the team started with gelatin. This springy protein is common in the bones and hooves of many animals, including pigs and cows. Every year, meat producers throw away large volumes of gelatin that doesn’t meet requirements for cosmetics or food products like Jell-O. (Lázaro Vásquez bought her own gelatin, which comes as a powder, from a local butcher shop).

She and her colleagues decided to turn that waste into wearable treasure.

The group’s machine uses a plastic syringe to heat up and squeeze out droplets of a liquid gelatin mixture. Two sets of rollers in the machine then tug on the gelatin, stretching it out into long, skinny fibers—not unlike a spider spinning a web from silk. In the process, the fibers also pass through liquid baths where the researchers can introduce bio-based dyes or other additives to the material. Adding a little bit of genipin, an extract from fruit, for example, makes the fibers stronger.

Dissolving duds

Lázaro Vásquez said designers may be able to do anything they can imagine with these sorts of textiles.

As a proof of concept, the researchers made small sensors out of gelatin fibers and cotton and conductive yarns, similar to the makeup of a Jacquard jacket. The team then submerged these patches in warm water. The gelatin dissolved, releasing the yarns for easy recycling and reuse.

Designers could tweak the chemistry of the fibers to make them a little more resilient, Lázaro Vásquez said—you wouldn’t want your jacket to disappear in the rain. [emphases mine] They could also play around with spinning similar fibers from other natural ingredients. Those materials include chitin, a component of crab shells, or agar-agar, which comes from algae.

“We’re trying to think about the whole lifecycle of our textiles,” Lázaro Vásquez said. “That begins with where the material is coming from. Can we get it from something that normally goes to waste?”

Here’s a link to and a citation for the paper,

Desktop Biofibers Spinning: An Open-Source Machine for Exploring Biobased Fibers and Their Application Towards Sustainable Smart Textile Design by Eldy S. Lazaro Vasquez, Mirela Alistar, Laura Devendorf, and Michael L. Rivera. CHI ’24: Proceedings of the CHI Conference on Human Factors in Computing Systems May 2024 Article No.: 856, Pages 1 – 18 DOI: https://doi.org/10.1145/3613904.3642387 Published: 11 May 2024

This paper is behind a paywall.

Let’s hope somebody (researcher or designer or ???) take a more extensive approach to solving the problem of fabrics that could dissolve prematurely.

Fashion, sustainability, and the protein threads that bind textiles and cosmetics

I’m starting with a somewhat enthusiastic overview of the role synthetic biology is playing in the world of clothing and cosmetics in The Scientist and following it up with some stories about fish leather, no synthetic biology involved but all of these stories are about sustainability and fashion and, in one case, cosmetics.

Fashionable synthetic biology

Meenakshi Prabhune’s June 14, 2024 article in The Scientist, in addition to the overview, provides information that explains how some of the work on textiles and leather is being used in the production of cosmetics. She starts with a little history/mythology and then launches into the synthetic biology efforts to produce silk and leather suitable for consumer use, Note: Links have been removed,

Once upon a time, circa 2700 BC in China, empress Xi Ling Shi was enjoying her afternoon tea under a mulberry tree, when a silkworm cocoon fell from the tree into her tea. She noticed that on contact with the hot beverage, the cocoon unraveled into a long silky thread. This happy accident inspired her to acquire these threads in abundance and fashion them into an elegant fabric. 

So goes the legend, according to the writings of Confucius, about the discovery of silk and the development of sericulture in ancient China. Although archaeological evidence from Chinese ruins dates the presence of silk to 8500 years ago, hinting that the royal discovery story was spun just like the silk fabric, one part of the legend rings true.1 The Chinese royals played a pivotal role in popularizing silk as a symbol of status and wealth. By 130 BC, emperors in the Ancient Civilizations across the world desired to be clad in silken garments, paving the Silk Road that opened trade routes from China to the West. 

While silk maintained its high-society status over the next thousands of years, the demand for easy-to-use materials grew among mass consumers. In the early 20th century, textile developers applied their new-found technological prowess to make synthetic materials: petrochemical-based polymer blended textiles with improved durability, strength, and convenience. 

In their quest to make silk powerful again, not by status but rather by thread strength, scientists turned to an arachnoid. Dragline silk, the thread by which the spider hangs itself from the web, is one of the strongest fibers; its tensile strength—a measure of how much a polymer deforms when strained—is almost thrice that of silkworm silk.2 

Beyond durable fashion garments, tough silk fibers are coveted in parachutes, military protective gear, and automobile safety belts, among other applications, so scientists are keen to pull on these threads. While traditional silk production relies on sericulture, arachnophobes can relax: spider farms are not a thing.

“Spiders make very little silk and are quite territorial. So, the only way to do it is to make microbes that make the protein,” said David Breslauer, cofounder and chief technology officer at Bolt Threads, a bio apparel company. 

For decades, researchers have coaxed microbes into churning their metabolites in large fermentation tanks, which they have harvested to solve dire crises in many areas. For instance, when pharmaceuticals struggled to meet the growing demand for insulin through the traditional methods of extraction from animal pancreas, researchers at Genentech sought the aid of E. coli to generate recombinant insulin for mass production in 1978.3  [emphases mine]

Prabhune’s June 14, 2024 article notes some difficulties with spider silk, Note: Links have been removed,

… researchers soon realized that producing spider silk in microbes was no easy feat. The spider silk protein, spidroin, is larger than 300 kDa in size—a huge jump from the small 6 kDa recombinant insulin. Bulky proteins impose a heavy metabolic load on the microbes and their production yield tanks. Also, spidroin consists of repeating regions of glycine and alanine amino acids that impart strength and elasticity to the material, but the host microbes struggle with protein folding and overexpression of the corresponding tRNA molecules.4  

… researchers had gotten close, but they hadn’t been able to synthesize the full spidroin protein. Since the molecular weight of the silk protein correlates with the strength of the silk thread, Zhang [Fuzhong Zhang, a synthetic biologist at Washington University in St. Louis] was determined to produce the entire protein to mimic the silk’s natural properties.5

To achieve this goal without pushing the metabolic limits of the bacteria, Zhang and his team literally broke down the problem. In 2018, they devised a recombinant spidroin by constructing two protein halves with split inteins—peptides known to catalyze ligation between proteins while splicing out their own residues—tagged at their ends. They synthesized the halves in separate E. coli cultures, mixed the two cultures, and ligated the proteins to yielded a recombinant spidroin of 556 kDa—a size that was previously considered unobtainable.6 The resulting silk fiber made from these recombinant spidroins matched the mechanical properties of natural spider silk fiber.

While synthesizing the high molecular weight protein validated their technical prowess and strategy, Zhang knew that the yield with this approach was going to be unavoidably low. “It was not even enough to make a simple shirt,” he said.

Zhang and his team did solve the problem of getting a higher yield but that led to another problem, from Prabhune’s June 14, 2024 article,

Breslauer echoed the importance of this step. He recalled how scaling up was the biggest challenge when he and his cofounder Dan Widmaier, chief executive officer at Bolt Threads, first set up shop in 2009. The duo met during their graduate studies. Breslauer, a material science student at the University of California, Berkeley, was fascinated by spider silk and sought help for synthesizing the protein in microbes. Luckily, he met Widmaier, a synthetic biology graduate student who was optimizing systems to study complex proteins.

When their collaboration to produce recombinant spider silk proteins in yeast yielded promising results, the duo decided to challenge the status quo in the textile industry by commercially producing bio-silk apparel, and Bolt Threads was born. The market transition, however, was not as smooth as the threads they produced. 

“There was so little innovation in the textile space, and brands were really eager to talk about innovation. It felt like there was demand there. Turns out, the desire for storytelling outweighed the desire for actual innovation with those brands,” Breslauer said. “We didn’t realize how adverse [sic] people were going to be to the idea because it was so unfamiliar.”

Prabhune’s June 14, 2024 article also covers leather and cosmetics, Note: Links have been removed,

David Williamson, a chemist and the chief operations officer at Modern Meadow and his team wanted to separate themselves from the herd. In their quest for sustainable alternatives, they went back to the basic biology and chemistry of the material. As leather is made from animal skin, it is rich in collagen, a structural protein abundant in the extracellular matrix of connective tissues. If the team could produce this primary component protein at scale, they would be able to process it into leather downstream. 

In about 2017, Williamson and his team developed a fermentation-based approach to produce collagen from yeast. While they achieved scalable production, there was one small hiccup. The protein properties of collagen alone did not yield the mechanical properties they needed for their leather-like material. 

The team went to the drawing board and analyzed the amino acid residues that contributed to collagen’s characteristics to look for a substitute protein. They found an alternative that had the desirable functional elements of collagen but was also sustainable and cost effective for industrial scale up: soy protein isolate. While tinkering with their recipes, they found the perfect combination for material strength by mixing in a bio-based polyurethane polymer with the protein to yield a refined bioalloy called Bio-VERA. 

As natural textiles are derived from animal skin, hair, or proteins, it is no surprise that many synthetic biologists in the textile space have also found a niche in cosmetics. Even as the Modern Meadow team transitioned away from their protein fermentation strategies to innovate Bio-VERA, they realized that they could still apply their expertise in skincare. While leathery is not an adjective one desires to associate with skin, collagen is an integral component in both. “When our bodies make collagen and build our extracellular matrices, one of the first proteins that they deposit is type three collagen. So, you can think of type three collagen almost like the structure or scaffold of a building,” explained Williamson.

To cater to the increasing demand for solutions to achieve younger looking skin, Williamson and his team engineered a recombinant collagen type three protein containing part of the protein sequence that is rich in binding domains for fibroblast interactions.9,10  “After you expose the extracellular matrix to this protein, it stimulates the fibroblasts to make more type three collagen. That type three collagen lays down type one collagen and elastin and fibronectin in a way that actually helps to turn back time, so to speak, to increase the ratio of type three collagen relative to type one collagen,” Williamson said. 

The Modern Meadow team are not the only ones to weave their textile strands into cosmetic applications. When Artur Cavaco-Paulo, a biological engineer at the University of Minho [Portugal], was studying wool fibers, he was struck by their structural similarities to human hair. “We decided that it would be a really good idea to transfer some of the knowledge that we had in wool textiles to human hair,” said Cavaco-Paulo. Particularly, he was interested in investigating solutions to fix hair strands damaged by highly alkaline chemical products. 

Over the next few years, Cavaco-Paulo developed […] shortlisted peptides into the K18 peptide product, which is now part of a commercially available leave-in conditioner. Cavaco-Paulo serves as the chief scientific officer at the biotech company K18. 

Although he started his career with textile research, Cavaco-Paulo favors the cosmetics sector with regards to returns on research and technology investment. “The personal care market is much more accustomed to innovation and has a much better and more fluid pipeline on innovation,” seconded Breslauer. “Whereas, [in] apparel, you really have to twist arms to get people to work with your material.” Bolt Threads ventured into the personal care space when Breslauer and his team serendipitously stumbled upon an alternative use for one of their textile proteins. 

While it’s not mentioned in Prabhune’s June 14, 2024 article, sustainability is mentioned on two of the company websites,

Bolt Threads

Bolt Threads is a material solutions company. With nature as our inspiration, we invent cutting-edge materials for the fashion and beauty industries to put us on a path toward a more sustainable future.

Through innovative collaborations with world-class brands and supply chain partners, we are on a mission to create way better materials for a way better world. Join us.

Modern Meadow

Modern Meadow is a climate-tech pioneer creating the future of materials through innovations in biology and material science.

​Our bio-materials technology platform with nature-inspired protein solutions delivers better performance, sustainability, scalability, and cost while reducing reliance on petrochemical and animal-based inputs.​

K18 has not adopted a ‘sustainability’ approach to marketing its hair care products.

Sustainability without synthetic biology: fish leather

In a January 3, 2022 posting I featured fish leather/skin in a story about the “Futures exhibition/festival” held at the Smithsonian Institute from November 20, 2021 to July 6, 2022.

Before getting to Futures, here’s a brief excerpt from a June 11, 2021 Smithsonian Magazine exhibition preview article by Gia Yetikyel about one of the contributors, Elisa Palomino-Perez (Note: A link has been removed),

Elisa Palomino-Perez sheepishly admits to believing she was a mermaid as a child. Growing up in Cuenca, Spain in the 1970s and ‘80s, she practiced synchronized swimming and was deeply fascinated with fish. Now, the designer’s love for shiny fish scales and majestic oceans has evolved into an empowering mission, to challenge today’s fashion industry to be more sustainable, by using fish skin as a material.

Luxury fashion is no stranger to the artist, who has worked with designers like Christian Dior, John Galliano and Moschino in her 30-year career. For five seasons in the early 2000s, Palomino-Perez had her own fashion brand, inspired by Asian culture and full of color and embroidery. It was while heading a studio for Galliano in 2002 that she first encountered fish leather: a material made when the skin of tuna, cod, carp, catfish, salmon, sturgeon, tilapia or pirarucu gets stretched, dried and tanned.

The history of using fish leather in fashion is a bit murky. The material does not preserve well in the archeological record, and it’s been often overlooked as a “poor person’s” material due to the abundance of fish as a resource. But Indigenous groups living on coasts and rivers from Alaska to Scandinavia to Asia have used fish leather for centuries. Icelandic fishing traditions can even be traced back to the ninth century. While assimilation policies, like banning native fishing rights, forced Indigenous groups to change their lifestyle, the use of fish skin is seeing a resurgence. Its rise in popularity in the world of sustainable fashion has led to an overdue reclamation of tradition for Indigenous peoples.

Brendan Jones provides an update of sorts in his Alaska-forward take in his February 22, 2024 article “Fish Leather Is Incredibly Strong and Beautiful. Can Makers ‘Scale Up’? Meet artisans in Alaska and BC who are sustaining, and advancing, an ancient art.” for The Tyee,

Fish leather artist June Pardue began her journey into the craft not knowing where to start. Which was a problem, considering that she had been given the job of demonstrating for tourists how to tan fish skin at the Alaska Native Heritage Center in Anchorage. “I couldn’t find anyone to teach me,” Pardue said with a laugh.

“One day a guy from Mississippi noticed me fumbling around. He kindly waited until everyone had left. Then he said, ‘Do you want me to share my grandpappy’s recipe for tanning snake skins?’”

His cocktail of alcohol and glycerin allowed her to soften the skins — as tourists looked on — for future use in clothing and bags. This worked fine until she began to grow uncomfortable dumping toxins down the drain. Now she uses plant-based tannins like those found in willow branches after the season’s first snowmelt. She harvests the branches gingerly, allowing the trees to survive for the next generation of fish tanners.

Pardue, who teaches at the University of Alaska, was born on Kodiak Island, off the southern coast of the state, in Old Harbor village. Alutiiq and Iñupiaq, she was raised in Akhiok, population about 50, and Old Harbor.

Following her bumpy start at the heritage center, Pardue has since gone on to become one of Alaska’s and Canada’s most celebrated instructors and practitioners in the field of fish leather, lighting the way for others in Alaska and Canada.

Among the people Pardue has advised is CEO and founder of 7 Leagues tannery Tasha Nathanson, who is based in Vancouver. She met with Pardue to share her idea of creating a business built on making fish leather into boots and other items for a large customer base.

Before making her move to open a business, Nathanson spent a year running the numbers, she said. In 2022, the global fish leather market was valued at US$36.22 million. As fish tanneries open their doors and fashion houses take notice, the number is expected to grow 16 per cent annually, topping $100 million by 2030.

“Salmon certainly don’t come to mind when you think of tanning, but people are catching on,” said Judith Lehmann, a Sitka-based expert in fish leather, who took Pardue’s class. (The Tyee reached Lehmann in Panama, where she was experimenting with skins of bonito and mahi mahi.)

Growing numbers of buyers are willing to pay for not only the beauty but also the remarkable durability fish leather can offer. California-based eco-fashion designer Hailey Harmon’s company Aitch Aitch sells the Amelia, a teal backpack made of panelled salmon leather, for $795.

One company in France has started to collect fish skins from restaurants — material that would otherwise end up in trash cans — to make luxury watch bands and accessories. Designers like Prada, Louis Vuitton and Christian Dior have incorporated fish leather into their lines. Even Nike introduced running shoes made of perch skin.

Whether they know it or not, today’s trendsetters are rooted in ancient history. “People have been working with fish skins for thousands of years,” Pardue said. “Ireland, Iceland, Norway, China, Japan — it’s an age-old practice.”

“On a molecular level, fibres in fish leather are cross-hatched, as opposed to cow leather, which is just parallel,” Nathanson explained. “So, pound for pound, this leather is stronger, which is great for shoes. And it’s more available, and eco-conscious. It’s a win across the board.”

Jones’s February 22, 2024 article has some wonderful embedded pictures and Beth Timmins’s May 1, 2019 article for the BBC (British Broadcasting Corporation), while a little dated, offers more information about the international scene.

Synthetic biology is a scientific practice that I find disconcerting at times. That said, I’m glad to see more work on sustainable products however they are derived. On that note I have a couple of recent stories:

  • “Three century long development of a scientific idea: body armor made from silk” is the title of my July 11, 2024 posting
  • “Grown from bacteria: plastic-free vegan leather that dyes itself” is the title of my June 26, 2024 posting

Enjoy!

Grown from bacteria: plastic-free vegan leather that dyes itself

Interesting rather than aesthetiically pleasing,

Caption: Bacteria grown and dyed shoe. Credit; Tom Ellis/Marcus Walker/Imperial College London

An April 3, 2024 news item on phys.org announces this latest example of bacterial footwear,

Researchers at Imperial College London have genetically engineered bacteria to grow animal- and plastic-free leather that dyes itself.

In recent years, scientists and companies have started using microbes to grow sustainable textiles or to make dyes for industry—but this is the first time bacteria have been engineered to produce a material and its own pigment simultaneously.

An April 3, 2024 Imperial College London (ICL) press release (also on EurekAlert) by Caroline Brogan, which originated the news item, delves further into the research, Note: Links have been removed,

Synthetic chemical dyeing is one of the most environmentally toxic processes in fashion, and black dyes – especially those used in colouring leather – are particularly harmful. The researchers at Imperial set out to use biology to solve this.

In tackling the problem, the researchers say their self-dyeing vegan, plastic-free leather, which has been fashioned into shoe and wallet prototypes, represents a step forward in the quest for more sustainable fashion.

Their new process, which has been published in the journal Nature Biotechnology, could also theoretically be adapted to have bacteria grow materials with various vibrant colours and patterns, and to make more sustainable alternatives to other textiles such as cotton and cashmere.

Lead author Professor Tom Ellis, from Imperial College London’s Department of Bioengineering, said: “Inventing a new, faster way to produce sustainable, self-dyed leather alternatives is a major achievement for synthetic biology and sustainable fashion.

“Bacterial cellulose is inherently vegan, and its growth requires a tiny fraction of the carbon emissions, water, land use and time of farming cows for leather.

“Unlike plastic-based leather alternatives, bacterial cellulose can also be made without petrochemicals, and will biodegrade safely and non-toxically in the environment.”

Designer collaboration

The researchers created the self-dyeing leather alternative by modifying the genes of a bacteria species that produces sheets of microbial cellulose – a strong, flexible and malleable material that is already commonly used in food, cosmetics and textiles. The genetic modifications ‘instructed’ the same microbes that were growing the material to also produce the dark black pigment, eumelanin.

They worked with designers to grow the upper part of a shoe (without the sole) by growing a sheet of bacterial cellulose in a bespoke, shoe-shaped vessel. After 14 days of growth wherein the cellulose took on the correct shape, they subjected the shoe to two days of gentle shaking at 30°C to activate the production of black pigment from the bacteria so that it dyed the material from the inside.

They also made a black wallet by growing two separate cellulose sheets, cutting them to size, and sewing them together.

As well as the prototypes, the researchers demonstrated that the bacteria can be engineered using genes from other microbes to produce colours in response to blue light. By projecting a pattern, or logo, onto the sheets using blue light, the bacteria respond by producing coloured proteins which then glow.

This allows them to project patterns and logos onto the bacterial cultures as the material grows, resulting in patterns and logos forming from within the material. 

Co-author Dr Kenneth Walker, who conducted the work at Imperial College London’s Department of Bioengineering and now works in industry, said: “Our technique works at large enough scales to create real-life products, as shown by our prototypes. From here, we can consider aesthetics as well as alternative shapes, patterns, textiles, and colours.

“The work also shows the impact that can happen when scientists and designers work together. As current and future users of new bacteria-grown textiles, designers have a key role in championing exciting new materials and giving expert feedback to improve form, function, and the switch to sustainable fashion.”

Greener clothes

The research team are now experimenting with a variety of coloured pigments to use those that can also be produced by the material-growing microbes.

The researchers and collaborators have also just won £2 million in funding from Biotechnology and Biological Sciences Research Council (BBSRC), part of UK Research and Innovation (UKRI), to use engineering biology and bacterial cellulose to solve more of fashion’s problems, such as the use of toxic chromium in leather’s production lines.

Professor Ellis said: “Microbes are already directly addressing many of the problems of animal and plastic-based leather, and we plan to get them ready to expand into new colours, materials and maybe patterns too.

“We look forward to working with the fashion industry to make the clothes we wear greener throughout the whole production line.”

The authors worked closely with Modern Synthesis, a London-based biodesign and materials company, who specialise in innovative microbial cellulose products.

This work was funded by Engineering and Physical Sciences Research Council and BBSRC, both part of UKRI.

Here’s a link to and a citation for the paper,

Self-pigmenting textiles grown from cellulose-producing bacteria with engineered tyrosinase expression by Kenneth T. Walker, Ivy S. Li, Jennifer Keane, Vivianne J. Goosens, Wenzhe Song, Koon-Yang Lee & Tom Ellis. Nature Biotechnology (2024) DOI: https://doi.org/10.1038/s41587-024-02194-3 Published: 02 April 2024

This paper is open access.

Modern Synthesis, the company with which the researchers collaborated, can be found here.

Textiles fight back bacteria with electronics

These textiles according to an April 24, 2023 news item on SpaceDaily do a little more than fight off bacteria (as impressive as that is),

Scientists from around the world have developed a simple metallic coating treatment for clothing or wearable textiles which can repair itself, repel dangerous bacteria from the wearer and even monitor a person’s electrocardiogram (ECG) heart signals.

Researchers from North Carolina State University [US], Flinders University [Australia] and South Korea [Sungkyunkwan University (SKKU] say the conductive circuits created by liquid metal (LM) particles can transform wearable electronics and open doors for further development of human-machine interfaces, including soft robotics and health monitoring systems.

An April 25, 2023 Flinders University press release (also on EurekAlert but published April 26, 2023), which originated the news item, provides more technical details about the conductive, self-healing textiles, Note: Links have been removed,

The ‘breathable’ electronic textiles have special connectivity powers to ‘autonomously heal’ itself even when cut, says the US team led by international expert in the field, Professor Michael Dickey.  

When the coated textiles are pressed with significant force, the particles merge into a conductive path, which enables the creation of circuits that can maintain conductivity when stretched, researchers say.   

“The conductive patterns autonomously heal when cut by forming new conductive paths along the edge of the cut, providing a self-healing feature which makes these textiles useful as circuit interconnects, Joule heaters and flexible electrodes to measure ECG signals,” says Flinders University medical biotechnology researcher Dr Khanh Truong, senior co-author in a new article in Advanced Materials Technologies. 

The technique involves dip-coating fabric into a suspension of LM particles at room temperature.  

“Evenly coated textiles remain electrically insulating due to the native oxide that forms on the LM particles. However, the insulating effect can be removed by compressing the textile to rupture the oxide and thereby allow the particles to percolate.  

“This enables the creation of conductive circuits by compressing the textile with a patterned mold. The electrical conductivity of the circuits increases by coating more particles on the textile.”  

As well the LM-coated textiles offer effective antimicrobial protection against Pseudomonas aeruginosa and Staphylococcus aureus.  

This germ repellent ability not only gives the treated fabric protective qualities but prevents the porous material from becoming contaminated if worn for and extended time, or put in contact with other people.    

The particles of gallium-based liquid metals have low melting point, metallic electrical conductivity, high thermal conductivity, effectively zero vapor pressure, low toxicity and antimicrobial properties.  

LMs have both fluidic and metallic properties so show great promise in applications such as microfluidics, soft composites, sensors, thermal switches and microelectronics.  

One of the advantages of LM is that it can be deposited and patterned at room temperature onto surfaces in unconventional ways that are not possible with solid metals. 

Here’s a link to and a citation for the paper,

Liquid Metal Coated Textiles with Autonomous Electrical Healing and Antibacterial Properties (2023) by Jiayi Yang, Praneshnandan Nithyanandam, Shreyas Kanetkar, Ki Yoon Kwon, Jinwoo Ma, Sooik Im, Ji-Hyun Oh, Mohammad Shamsi, Mike Wilkins, Michael Daniele Tae-il Kim, Huu Ngoc Nguyen, Vi Khanh Truong and Michael D Dickey. Advanced Materials Technologies Online Version of Record before inclusion in an issue 2202183 DOI: 10.1002/admt.202202183 First published: 02 April 2023 [2nd DOI:] https://doi.org/10.1002/admt.202202183 

This paper is open access.

Carbon nanotubes and stab-resistant fabric

The use of carbon nanotubes (CNTs) in protective clothing is not new (see my November 4, 2013 post titled, “A $20,000+, bulletproof, carbon nanotube-enabled business suit from a Toronto-based company (Canada) being tested Nov. 5, 2013“).

This is, however, the first time I’ve seen CNTs used for ‘stab-resistant’ clothing. From an April 19, 2023 news item on ScienceDaily,

Fabrics that resist knife cuts can help prevent injuries and save lives. But a sharp enough knife or a very forceful jab can get through some of these materials. Now, researchers report in ACS Applied Nano Materials that carbon nanotubes and polyacrylate strengthen conventional aramid to produce lightweight, soft fabrics that provide better protection. Applications include anti-stabbing clothing, helmets and insoles, as well as cut-resistant packaging.

An April 19, 2023 American Chemical Society (ACS) news release (also on EurekAlert), which originated the news item, describes the current situation with body armo(u)r and how this research could change things,

Soft body armor is typically made from aramid, ultra-high-molecular-weight polyethylene, or carbon and glass fabrics. Their puncture resistance depends, in part, on the friction between yarn fibers within these materials. Up to a point, greater friction means greater protection. Manufacturers can boost friction by roughening the fiber surfaces, but that requires a complicated process, and product yield is low. Alternatively, the bonding force between yarns can be enhanced by adding another component, such as a sheer thickening fluid (STF) or a polyurethane (PU) coating. But these composite fabrics can’t simultaneously satisfy the requirements for thinness, flexibility and light weight. Ting-Ting Li, Xing-xiang Zhang and colleagues wanted to find another way to improve performance while satisfying these criteria.

The researchers tested a polyacrylate emulsion (PAE), STF and PU as coatings on aramid fabric. In simulated stabbing tests, aramid fabric coated with PAE outperformed the uncoated material used by itself or in combination with STF or PU. Carbon nanotubes are known to make composites tougher, and adding them to aramid/PAE further improved impact resistance. The team says that’s because the nanotubes created bridges between the fibers, thereby increasing friction. The nanotubes also formed a thin, protective network that dispersed stress away from the point of impact and helped prevent fiber disintegration. The new lightweight, flexible, puncture-resistant composite fabric could be useful in military and civilian applications, according to the researchers.

Here’s a link to and a citation for the paper,

Polyacrylate and Carboxylic Multi-Walled Carbon Nanotube-Strengthened Aramid Fabrics as Flexible Puncture-Resistant Composites for Anti-Stabbing Applications by Wen-hua Cai, Ting-ting Li, and Xing-xiang Zhang. ACS Appl. Nano Mater. 2023, 6, 7, 6334–6344 DOI: https://doi.org/10.1021/acsanm.3c00738 Publication Date:April 5, 2023 Copyright © 2023 American Chemical Society

This paper is behind a paywall.