Tag Archives: sciences
#434823 The Tangled Web of Turning Spider Silk ...
Spider-Man is one of the most popular superheroes of all time. It’s a bit surprising given that one of the more common phobias is arachnophobia—a debilitating fear of spiders.
Perhaps more fantastical is that young Peter Parker, a brainy high school science nerd, seemingly developed overnight the famous web-shooters and the synthetic spider silk that he uses to swing across the cityscape like Tarzan through the jungle.
That’s because scientists have been trying for decades to replicate spider silk, a material that is five times stronger than steel, among its many superpowers. In recent years, researchers have been untangling the protein-based fiber’s structure down to the molecular level, leading to new insights and new potential for eventual commercial uses.
The applications for such a material seem near endless. There’s the more futuristic visions, like enabling robotic “muscles” for human-like movement or ensnaring real-life villains with a Spider-Man-like web. Near-term applications could include the biomedical industry, such as bandages and adhesives, and as a replacement textile for everything from rope to seat belts to parachutes.
Spinning Synthetic Spider Silk
Randy Lewis has been studying the properties of spider silk and developing methods for producing it synthetically for more than three decades. In the 1990s, his research team was behind cloning the first spider silk gene, as well as the first to identify and sequence the proteins that make up the six different silks that web slingers make. Each has different mechanical properties.
“So our thought process was that you could take that information and begin to to understand what made them strong and what makes them stretchy, and why some are are very stretchy and some are not stretchy at all, and some are stronger and some are weaker,” explained Lewis, a biology professor at Utah State University and director of the Synthetic Spider Silk Lab, in an interview with Singularity Hub.
Spiders are naturally territorial and cannibalistic, so any intention to farm silk naturally would likely end in an orgy of arachnid violence. Instead, Lewis and company have genetically modified different organisms to produce spider silk synthetically, including inserting a couple of web-making genes into the genetic code of goats. The goats’ milk contains spider silk proteins.
The lab also produces synthetic spider silk through a fermentation process not entirely dissimilar to brewing beer, but using genetically modified bacteria to make the desired spider silk proteins. A similar technique has been used for years to make a key enzyme in cheese production. More recently, companies are using transgenic bacteria to make meat and milk proteins, entirely bypassing animals in the process.
The same fermentation technology is used by a chic startup called Bolt Threads outside of San Francisco that has raised more than $200 million for fashionable fibers made out of synthetic spider silk it calls Microsilk. (The company is also developing a second leather-like material, Mylo, using the underground root structure of mushrooms known as mycelium.)
Lewis’ lab also uses transgenic silkworms to produce a kind of composite material made up of the domesticated insect’s own silk proteins and those of spider silk. “Those have some fairly impressive properties,” Lewis said.
The researchers are even experimenting with genetically modified alfalfa. One of the big advantages there is that once the spider silk protein has been extracted, the remaining protein could be sold as livestock feed. “That would bring the cost of spider silk protein production down significantly,” Lewis said.
Building a Better Web
Producing synthetic spider silk isn’t the problem, according to Lewis, but the ability to do it at scale commercially remains a sticking point.
Another challenge is “weaving” the synthetic spider silk into usable products that can take advantage of the material’s marvelous properties.
“It is possible to make silk proteins synthetically, but it is very hard to assemble the individual proteins into a fiber or other material forms,” said Markus Buehler, head of the Department of Civil and Environmental Engineering at MIT, in an email to Singularity Hub. “The spider has a complex spinning duct in which silk proteins are exposed to physical forces, chemical gradients, the combination of which generates the assembly of molecules that leads to silk fibers.”
Buehler recently co-authored a paper in the journal Science Advances that found dragline spider silk exhibits different properties in response to changes in humidity that could eventually have applications in robotics.
Specifically, spider silk suddenly contracts and twists above a certain level of relative humidity, exerting enough force to “potentially be competitive with other materials being explored as actuators—devices that move to perform some activity such as controlling a valve,” according to a press release.
Studying Spider Silk Up Close
Recent studies at the molecular level are helping scientists learn more about the unique properties of spider silk, which may help researchers develop materials with extraordinary capabilities.
For example, scientists at Arizona State University used magnetic resonance tools and other instruments to image the abdomen of a black widow spider. They produced what they called the first molecular-level model of spider silk protein fiber formation, providing insights on the nanoparticle structure. The research was published last October in Proceedings of the National Academy of Sciences.
A cross section of the abdomen of a black widow (Latrodectus Hesperus) spider used in this study at Arizona State University. Image Credit: Samrat Amin.
Also in 2018, a study presented in Nature Communications described a sort of molecular clamp that binds the silk protein building blocks, which are called spidroins. The researchers observed for the first time that the clamp self-assembles in a two-step process, contributing to the extensibility, or stretchiness, of spider silk.
Another team put the spider silk of a brown recluse under an atomic force microscope, discovering that each strand, already 1,000 times thinner than a human hair, is made up of thousands of nanostrands. That helps explain its extraordinary tensile strength, though technique is also a factor, as the brown recluse uses a special looping method to reinforce its silk strands. The study also appeared last year in the journal ACS Macro Letters.
Making Spider Silk Stick
Buehler said his team is now trying to develop better and faster predictive methods to design silk proteins using artificial intelligence.
“These new methods allow us to generate new protein designs that do not naturally exist and which can be explored to optimize certain desirable properties like torsional actuation, strength, bioactivity—for example, tissue engineering—and others,” he said.
Meanwhile, Lewis’ lab has discovered a method that allows it to solubilize spider silk protein in what is essentially a water-based solution, eschewing acids or other toxic compounds that are normally used in the process.
That enables the researchers to develop materials beyond fiber, including adhesives that “are better than an awful lot of the current commercial adhesives,” Lewis said, as well as coatings that could be used to dampen vibrations, for example.
“We’re making gels for various kinds of of tissue regeneration, as well as drug delivery, and things like that,” he added. “So we’ve expanded the use profile from something beyond fibers to something that is a much more extensive portfolio of possible kinds of materials.”
And, yes, there’s even designs at the Synthetic Spider Silk Lab for developing a Spider-Man web-slinger material. The US Navy is interested in non-destructive ways of disabling an enemy vessel, such as fouling its propeller. The project also includes producing synthetic proteins from the hagfish, an eel-like critter that exudes a gelatinous slime when threatened.
Lewis said that while the potential for spider silk is certainly headline-grabbing, he cautioned that much of the hype is not focused on the unique mechanical properties that could lead to advances in healthcare and other industries.
“We want to see spider silk out there because it’s a unique material, not because it’s got marketing appeal,” he said.
Image Credit: mycteria / Shutterstock.com Continue reading
#433798 Five Things We Know About the State of ...
From drug development to food science and genetics, the life sciences industry is alive and innovating in 2018. According to a recent report, emerging technologies offer the most potential for this vital sector. As we enter a ‘fourth industrial revolution’, Artificial Intelligence (AI) and other next-generation technologies are boosting productivity and pushing the boundaries of …
The post Five Things We Know About the State of the Life Sciences Industry Today appeared first on TFOT. Continue reading
#433594 Technology and Compassion: A ...
From how we get around to how we spend our time to how we manage our health, technology is changing our lives—not to mention economies, governments, and cities around the world. Tech has brought good to individuals and societies by, for example, democratizing access to information and lowering the cost of many products and services. But it’s also brought less-desirable effects we can’t ignore, like a rise in mental health problems and greater wealth inequality.
To keep pushing tech in a direction that will benefit humanity as a whole—rather than benefiting a select few—we must encourage open dialogues about these topics among leading figures in business, government, and spirituality.
To that end, SingularityU The Netherlands recently hosted a dialogue about compassion and technology with His Holiness the Dalai Lama. The event was attended by students and tech innovators, ambassadors, members of the Dutch royal family, and other political and business leaders.
The first half of the conversation focused on robotics, telepresence, and artificial intelligence. His Holiness spoke with Tilly Lockey, a British student helping tech companies create bionic limbs, Karen Dolva, CEO of telepresence company No Isolation, and Maarten Steinbuch, faculty chair of robotics at SingularityU the Netherlands and a professor of systems and control at TU Eindhoven.
When asked what big tech companies could be doing to help spread good around the world, His Holiness pointed out that while technology has changed many aspects of life in developed countries, there is still immense suffering in less-developed nations, and tech companies should pay more attention to the poorer communities around the world.
In the second half of the event, focus switched to sickness, aging, and death. Speakers included Liz Parrish, CEO of BioViva Sciences, Kris Verburgh, faculty chair of health and medicine at SingularityU the Netherlands, Jeantine Lunshof, a bio-ethicist at MIT Media Lab, and Selma Boulmalf, a religious studies student at University of Amsterdam. Among other topics, they talked with His Holiness about longevity research and the drawbacks of trying to extend our lifespans or achieve immortality.
Both sessions were moderated by Christa Meindersma, founder and chair of the Himalaya Initiative for Culture and Society. The event served as the ceremonial opening of an exhibition called The Life of the Buddha, Path to the Present, on display in Amsterdam’s 15-century De Nieuwe Kerk church through February 2019.
In the 21st century, His Holiness said, “There is real possibility to create a happier world, peaceful world. So now we need vision. A peaceful world on the basis of a sense of oneness of humanity.”
Technology’s role in that world is being developed and refined every day, and we must maintain an ongoing awareness of its positive and negative repercussions—on everyone.
Image Credit: vipflash / Shutterstock.com Continue reading
#431824 iCub Humanoid Platform for RobotCub
The iCub platform was developed for the EU project RobotCub, and the humanoid is able to see and hear, and it has the sense of proprioception (Wikipedia: “the sense of the relative position of one’s own parts of the body … Continue reading