Now in its twelfth year, the international conference “Living Machines”, organised by Istituto Italiano di Tecnologia (Italian Institute of Technology, IIT), returns to Italy and comes to Genoa for the first time, from 10 to 13 July. Around one hundred experts from all over the world are expected, and they will present their achievements in the field of bio-inspired science and technology. The conference will take place in an exceptional venue, the Acquario di Genova (Genoa Aquarium), which, having reached its 30th birthday, is the ideal location at which to bring together various subject areas, from biology to artificial intelligence and robotics, with a focus on sustainability and environmental protection.
The scientific organiser of the event is Barbara Mazzolai, Associate Director for Robotics and head of the Bioinspired Soft Robotics Lab at IIT, along with Fabian Meder, researcher in the Bioinspired Soft Robotics Lab group and co-chair of the conference programme.
The conference will include two events open to the public: an exhibition area, which will be accessible from 11 to 13 July in the afternoon (from 2 to 4.30 pm); and a scientific café, which will take place on the 12 July at 5 pm. The conference will be an opportunity for international guests to appreciate the region’s beauty and talents, and it will also include the participation of students from the Niccolò Paganini Conservatory of Music. In addition, a satellite event of the conference will be the ISPA – Italian Sustainability Photo Award – exhibition, which will open at Palazzo Ducale on 10 July at 6 p.m.
The “Living Machines” conference is the landmark event for the international scientific community which bases its research on living organisms, such as human beings and other animal species – terrestrial, marine, and airborne – in addition to plants, fungi, and bacteria, in order to create so-called “living machines”, in other words, forms of technology capable of replicating their structure and mechanisms of operation.
“The conference is rooted in the union between robotics and neuroscience, using man and other animal species as a model for the study of intelligence and control systems,” said Barbara Mazzolai, Associate Director for Robotics at IIT. “This year the conference will focus on the role of biomimicry in the creation of robots that are more sustainable, with applications for the challenges of environmental protection and human health. Discussions will revolve around the development of robots with a lower energy impact, made using recyclable and biodegradable materials, and that can be used in emergency situations or extreme environments, such as deep sea, soil, space, or environmental disasters, but also for precision agriculture, environmental surveillance, infrastructure monitoring, human care and medical-surgical assistance.”
In the conference programme, experts will take part in a first day of parallel workshop and tutorial sessions (on 10 July), during which the topics of bioinspiration and biohybrid technology in the fields of medicine and the marine environment will be addressed. This first day will be followed by three days of plenary sessions, featuring talks by internationally-renowned scientists. More specifically: Oussama Khatib, one of the pioneers of robotics and director of the Robotics Laboratory at Stanford University; Marco Dorigo, professor at the Université Libre de Bruxelles and one of the pioneers of collective intelligence; Peter Fratzl, director of the Max Planck Institute of Colloids and Interfaces, working on research into osteoporosis and tissue regeneration; Eleni Stavrinidou, coordinator of the “Electronic Plants” group at Linköping University and an expert in bioelectronic and biohybrid systems; Olga Speck, Principal Researcher at the University of Freiburg, specialising in biomimetic materials and the regenerative capabilities of plants; and Kyu-Jin Cho, director of the Research Centre for Soft Robotics and the Biorobotics Laboratory at Seoul National University, one of the world’s leading experts on soft robotics.
For conference participants only, the programme includes: a visit to the Acquario, guided by the facility’s scientific staff, who will illustrate the work and practices needed for the protection and conservation of marine species and the undergoing research projects; an exhibition area for prototypes and products by research groups and companies operating in this field; and a dinner at Villa Lo Zerbino, with a musical contribution by students from the Niccolò Paganini Conservatory.
Open to the general public, on 12 July from 5 p.m. to 6 p.m. there will be a round table entitled “Living Machines: The Origin and the Future” chaired by science journalist Nicola Nosengo, Chief Editor of Nature Italy. Speakers will include Cecilia Laschi from the National University of Singapore, Vickie Webster-Wood from Carnegie Mellon University, Thomas Speck from the University of Freiburg and Paul Verschure from Radboud University Nijmegen.
A satellite initiative of the conference will be the exhibition for ISPA, the Italian Sustainability Photo Award, which will open at Palazzo Ducale on 10 July at 6.00 p.m. ISPA is the photographic award created by the Parallelozero agency in cooperation with the main sponsor PIMCO, to raise public awareness of environmental, social, and governance sustainability issues, encapsulated in the acronym ESG. The works of the winning photographers and finalists in the last three editions will be on display in Genoa: a selection of images that depict the emblematic stories of Italy, a nation moving towards a more sustainable future, a visual narrative that makes it easier to understand the country’s progress in research and innovation.
The organisations supporting the event include, in addition to the principal organiser Istituto Italiano di Tecnologia (Italian Institute of Technology), the international Convergent Science Network [emphasis mine], the Office of Naval Research, Radboud University Nijmegen, and the Living, Adaptive and Energy-autonomous Materials Systems Cluster of Excellence in Freiburg.
I was particularly struck by this quote, “The conference is rooted in the union between robotics and neuroscience [emphasis mine], using man and other animal species as a model for the study of intelligence and control systems,” from Barbara Mazzolai as I have an as yet unpublished post for a UNESCO neurotechnology event coming up on July 13, 2023. These events come on the heels of a May 16, 2023 Canadian Science Policy Centre panel discussion on responsible neurotechnology (see my May 12, 2023 posting).
“We put nanotubes inside of bacteria,” says Professor Ardemis Boghossian at EPFL’s School of Basic Sciences. “That doesn’t sound very exciting on the surface, but it’s actually a big deal. Researchers have been putting nanotubes in mammalian cells that use mechanisms like endocytosis, that are specific to those kinds of cells. Bacteria, on the other hand, don’t have these mechanisms and face additional challenges in getting particles through their tough exterior. Despite these barriers, we’ve managed to do it, and this has very exciting implications in terms of applications.”
Boghossian’s research focuses on interfacing artificial nanomaterials with biological constructs, including living cells. The resulting “nanobionic” technologies combine the advantages of both the living and non-living worlds. For years, her group has worked on the nanomaterial applications of single-walled carbon nanotubes (SWCNTs), tubes of carbon atoms with fascinating mechanical and optical properties.
These properties make SWCNTs [single-walled carbon nanotubes] ideal for many novel applications in the field of nanobiotechnology. For example, SWCNTs have been placed inside mammalian cells to monitor their metabolisms using near-infrared imaging. The insertion of SWCNTs in mammalian cells has also led to new technologies for delivering therapeutic drugs to their intracellular targets, while in plant cells they have been used for genome editing. SWCNTs have also been implanted in living mice to demonstrate their ability to image biological tissue deep inside the body.
Fluorescent nanotubes in bacteria: A first
In an article published in Nature Nanotechnology, Boghossian’s group with their international colleagues were able to “convince” bacteria to spontaneously take up SWCNTs by “decorating” them with positively charged proteins that are attracted by the negative charge of the bacteria’s outer membrane. The two types of bacteria explored in the study, Synechocystis and Nostoc, belong to the Cyanobacteria phylum, an enormous group of bacteria that get their energy through photosynthesis – like plants. They are also “Gram-negative”, which means that their cell wall is thin, and they have an additional outer membrane that “Gram-positive” bacteria lack.
The researchers observed that the cyanobacteria internalized SWCNTs through a passive, length-dependent and selective process. This process allowed the SWCNTs to spontaneously penetrate the cell walls of both the unicellular Synechocystis and the long, snake-like, multicellular Nostoc.
Following this success, the team wanted to see if the nanotubes can be used to image cyanobacteria – as is the case with mammalian cells. “We built a first-of-its-kind custom setup that allowed us to image the special near-infrared fluorescence we get from our nanotubes inside the bacteria,” says Boghossian.
Alessandra Antonucci, a former PhD student at Boghossian’s lab adds: “When the nanotubes are inside the bacteria, you could very clearly see them, even though the bacteria emit their own light. This is because the wavelengths of the nanotubes are far in the red, the near-infrared. You get a very clear and stable signal from the nanotubes that you can’t get from any other nanoparticle sensor. We’re excited because we can now use the nanotubes to see what is going on inside of cells that have been difficult to image using more traditional particles or proteins. The nanotubes give off a light that no natural living material gives off, not at these wavelengths, and that makes the nanotubes really stand out in these cells.”
“Inherited nanobionics”
The scientists were able to track the growth and division of the cells by monitoring the bacteria in real-time. Their findings revealed that the SWCNTs were being shared by the daughter cells of the dividing microbe. “When the bacteria divide, the daughter cells inherent the nanotubes along with the properties of the nanotubes,” says Boghossian. “We call this ‘inherited nanobionics.’ It’s like having an artificial limb that gives you capabilities beyond what you can achieve naturally. And now imagine that your children can inherit its properties from you when they are born. Not only did we impart the bacteria with this artificial behavior, but this behavior is also inherited by their descendants. It’s our first demonstration of inherited nanobionics.”
Living photovoltaics
“Another interesting aspect is when we put the nanotubes inside the bacteria, the bacteria show a significant enhancement in the electricity it produces when it is illuminated by light,” says Melania Reggente, a postdoc with Boghossian’s group. “And our lab is now working towards the idea of using these nanobionic bacteria in a living photovoltaic.”
“Living” photovoltaics are biological energy-producing devices that use photosynthetic microorganisms. Although still in the early stages of development, these devices represent a real solution to our ongoing energy crisis and efforts against climate change.
“There’s a dirty secret in photovoltaic community,” says Boghossian. “It is green energy, but the carbon footprint is really high; a lot of CO2 is released just to make most standard photovoltaics. But what’s nice about photosynthesis is not only does it harness solar energy, but it also has a negative carbon footprint. Instead of releasing CO2, it absorbs it. So it solves two problems at once: solar energy conversion and CO2 sequestration. And these solar cells are alive. You do not need a factory to build each individual bacterial cell; these bacteria are self-replicating. They automatically take up CO2 to produce more of themselves. This is a material scientist’s dream.”
Boghossian envisions a living photovoltaic device based on cyanobacteria that have automated control over electricity production that does not rely on the addition of foreign particles. “In terms of implementation, the bottleneck now is the cost and environmental effects of putting nanotubes inside of cyanobacteria on a large scale.”
With an eye towards large-scale implementation, Boghossian and her team are looking to synthetic biology for answers: “Our lab is now working towards bioengineering cyanobacteria that can produce electricity without the need for nanoparticle additives. Advancements in synthetic biology allow us to reprogram these cells to behave in totally artificial ways. We can engineer them so that producing electricity is literally in their DNA.”
Other contributors
University of Freiburg Swiss Center for Electronics and Microtechnology University of Salento Sapienza University of Rome
Researchers at Stanford University (California, US) believe they have a solution for a problem with neuroprosthetics (Note: I have included brief comments about neuroprosthetics and possible ethical issues at the end of this posting) according an August 5, 2020 news item on ScienceDaily,
The current generation of neural implants record enormous amounts of neural activity, then transmit these brain signals through wires to a computer. But, so far, when researchers have tried to create wireless brain-computer interfaces to do this, it took so much power to transmit the data that the implants generated too much heat to be safe for the patient. A new study suggests how to solve his problem — and thus cut the wires.
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Caption: Photo of a current neural implant, that uses wires to transmit information and receive power. New research suggests how to one day cut the wires. Credit: Sergey Stavisky
Stanford researchers have been working for years to advance a technology that could one day help people with paralysis regain use of their limbs, and enable amputees to use their thoughts to control prostheses and interact with computers.
The team has been focusing on improving a brain-computer interface, a device implanted beneath the skull on the surface of a patient’s brain. This implant connects the human nervous system to an electronic device that might, for instance, help restore some motor control to a person with a spinal cord injury, or someone with a neurological condition like amyotrophic lateral sclerosis, also called Lou Gehrig’s disease.
The current generation of these devices record enormous amounts of neural activity, then transmit these brain signals through wires to a computer. But when researchers have tried to create wireless brain-computer interfaces to do this, it took so much power to transmit the data that the devices would generate too much heat to be safe for the patient.
Now, a team led by electrical engineers and neuroscientists Krishna Shenoy, PhD, and Boris Murmann, PhD, and neurosurgeon and neuroscientist Jaimie Henderson, MD, have shown how it would be possible to create a wireless device, capable of gathering and transmitting accurate neural signals, but using a tenth of the power required by current wire-enabled systems. These wireless devices would look more natural than the wired models and give patients freer range of motion.
Graduate student Nir Even-Chen and postdoctoral fellow Dante Muratore, PhD, describe the team’s approach in a Nature Biomedical Engineering paper.
The team’s neuroscientists identified the specific neural signals needed to control a prosthetic device, such as a robotic arm or a computer cursor. The team’s electrical engineers then designed the circuitry that would enable a future, wireless brain-computer interface to process and transmit these these carefully identified and isolated signals, using less power and thus making it safe to implant the device on the surface of the brain.
To test their idea, the researchers collected neuronal data from three nonhuman primates and one human participant in a (BrainGate) clinical trial.
As the subjects performed movement tasks, such as positioning a cursor on a computer screen, the researchers took measurements. The findings validated their hypothesis that a wireless interface could accurately control an individual’s motion by recording a subset of action-specific brain signals, rather than acting like the wired device and collecting brain signals in bulk.
The next step will be to build an implant based on this new approach and proceed through a series of tests toward the ultimate goal.
As I found out while investigating, ethical issues in this area abound. My first thought was to look at how someone with a focus on ability studies might view the complexities.
My ‘go to’ resource for human enhancement and ethical issues is Gregor Wolbring, an associate professor at the University of Calgary (Alberta, Canada). his profile lists these areas of interest: ability studies, disability studies, governance of emerging and existing sciences and technologies (e.g. neuromorphic engineering, genetics, synthetic biology, robotics, artificial intelligence, automatization, brain machine interfaces, sensors) and more.
I can’t find anything more recent on this particular topic but I did find an August 10, 2017 essay for The Conversation where he comments on technology and human enhancement ethical issues where the technology is gene-editing. Regardless, he makes points that are applicable to brain-computer interfaces (human enhancement), Note: Links have been removed),
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Ability expectations have been and still are used to disable, or disempower, many people, not only people seen as impaired. They’ve been used to disable or marginalize women (men making the argument that rationality is an important ability and women don’t have it). They also have been used to disable and disempower certain ethnic groups (one ethnic group argues they’re smarter than another ethnic group) and others.
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A recent Pew Research survey on human enhancement revealed that an increase in the ability to be productive at work was seen as a positive. What does such ability expectation mean for the “us” in an era of scientific advancements in gene-editing, human enhancement and robotics?
Which abilities are seen as more important than others?
The ability expectations among “us” will determine how gene-editing and other scientific advances will be used.
And so how we govern ability expectations, and who influences that governance, will shape the future. Therefore, it’s essential that ability governance and ability literacy play a major role in shaping all advancements in science and technology.
One of the reasons I find Gregor’s commentary so valuable is that he writes lucidly about ability and disability as concepts and poses what can be provocative questions about expectations and what it is to be truly abled or disabled. You can find more of his writing here on his eponymous (more or less) blog.
Ethics of clinical trials for testing brain implants
In 2003, neurologist Helen Mayberg of Emory University in Atlanta began to test a bold, experimental treatment for people with severe depression, which involved implanting metal electrodes deep in the brain in a region called area 25 [emphases mine]. The initial data were promising; eventually, they convinced a device company, St. Jude Medical in Saint Paul, to sponsor a 200-person clinical trial dubbed BROADEN.
This month [October 2017], however, Lancet Psychiatry reported the first published data on the trial’s failure. The study stopped recruiting participants in 2012, after a 6-month study in 90 people failed to show statistically significant improvements between those receiving active stimulation and a control group, in which the device was implanted but switched off.
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… a tricky dilemma for companies and research teams involved in deep brain stimulation (DBS) research: If trial participants want to keep their implants [emphases mine], who will take responsibility—and pay—for their ongoing care? And participants in last week’s meeting said it underscores the need for the growing corps of DBS researchers to think long-term about their planned studies.
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… participants bear financial responsibility for maintaining the device should they choose to keep it, and for any additional surgeries that might be needed in the future, Mayberg says. “The big issue becomes cost [emphasis mine],” she says. “We transition from having grants and device donations” covering costs, to patients being responsible. And although the participants agreed to those conditions before enrolling in the trial, Mayberg says she considers it a “moral responsibility” to advocate for lower costs for her patients, even it if means “begging for charity payments” from hospitals. And she worries about what will happen to trial participants if she is no longer around to advocate for them. “What happens if I retire, or get hit by a bus?” she asks.
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There’s another uncomfortable possibility: that the hypothesis was wrong [emphases mine] to begin with. A large body of evidence from many different labs supports the idea that area 25 is “key to successful antidepressant response,” Mayberg says. But “it may be too simple-minded” to think that zapping a single brain node and its connections can effectively treat a disease as complex as depression, Krakauer [John Krakauer, a neuroscientist at Johns Hopkins University in Baltimore, Maryland] says. Figuring that out will likely require more preclinical research in people—a daunting prospect that raises additional ethical dilemmas, Krakauer says. “The hardest thing about being a clinical researcher,” he says, “is knowing when to jump.”
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Brain-computer interfaces, symbiosis, and ethical issues
This was the most recent and most directly applicable work that I could find. From a July 24, 2019 article by Liam Drew for Nature Outlook: The brain,
“It becomes part of you,” Patient 6 said, describing the technology that enabled her, after 45 years of severe epilepsy, to halt her disabling seizures. Electrodes had been implanted on the surface of her brain that would send a signal to a hand-held device when they detected signs of impending epileptic activity. On hearing a warning from the device, Patient 6 knew to take a dose of medication to halt the coming seizure.
“You grow gradually into it and get used to it, so it then becomes a part of every day,” she told Frederic Gilbert, an ethicist who studies brain–computer interfaces (BCIs) at the University of Tasmania in Hobart, Australia. “It became me,” she said. [emphasis mine]
Gilbert was interviewing six people who had participated in the first clinical trial of a predictive BCI to help understand how living with a computer that monitors brain activity directly affects individuals psychologically1. Patient 6’s experience was extreme: Gilbert describes her relationship with her BCI as a “radical symbiosis”.
Symbiosis is a term, borrowed from ecology, that means an intimate co-existence of two species for mutual advantage. As technologists work towards directly connecting the human brain to computers, it is increasingly being used to describe humans’ potential relationship with artificial intelligence.
Interface technologies are divided into those that ‘read’ the brain to record brain activity and decode its meaning, and those that ‘write’ to the brain to manipulate activity in specific regions and affect their function.
Commercial research is opaque, but scientists at social-media platform Facebook are known to be pursuing brain-reading techniques for use in headsets that would convert users’ brain activity into text. And neurotechnology companies such as Kernel in Los Angeles, California, and Neuralink, founded by Elon Musk in San Francisco, California, predict bidirectional coupling in which computers respond to people’s brain activity and insert information into their neural circuitry. [emphasis mine]
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Already, it is clear that melding digital technologies with human brains can have provocative effects, not least on people’s agency — their ability to act freely and according to their own choices. Although neuroethicists’ priority is to optimize medical practice, their observations also shape the debate about the development of commercial neurotechnologies.
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Neuroethicists began to note the complex nature of the therapy’s side effects. “Some effects that might be described as personality changes are more problematic than others,” says Maslen [Hannah Maslen, a neuroethicist at the University of Oxford, UK]. A crucial question is whether the person who is undergoing stimulation can reflect on how they have changed. Gilbert, for instance, describes a DBS patient who started to gamble compulsively, blowing his family’s savings and seeming not to care. He could only understand how problematic his behaviour was when the stimulation was turned off.
Such cases present serious questions about how the technology might affect a person’s ability to give consent to be treated, or for treatment to continue. [emphases mine] If the person who is undergoing DBS is happy to continue, should a concerned family member or doctor be able to overrule them? If someone other than the patient can terminate treatment against the patient’s wishes, it implies that the technology degrades people’s ability to make decisions for themselves. It suggests that if a person thinks in a certain way only when an electrical current alters their brain activity, then those thoughts do not reflect an authentic self.
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To observe a person with tetraplegia bringing a drink to their mouth using a BCI-controlled robotic arm is spectacular. [emphasis mine] This rapidly advancing technology works by implanting an array of electrodes either on or in a person’s motor cortex — a brain region involved in planning and executing movements. The activity of the brain is recorded while the individual engages in cognitive tasks, such as imagining that they are moving their hand, and these recordings are used to command the robotic limb.
If neuroscientists could unambiguously discern a person’s intentions from the chattering electrical activity that they record in the brain, and then see that it matched the robotic arm’s actions, ethical concerns would be minimized. But this is not the case. The neural correlates of psychological phenomena are inexact and poorly understood, which means that signals from the brain are increasingly being processed by artificial intelligence (AI) software before reaching prostheses.[emphasis mine]
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But, he [Philipp Kellmeyer, a neurologist and neuroethicist at the University of Freiburg, Germany] says, using AI tools also introduces ethical issues of which regulators have little experience. [emphasis mine] Machine-learning software learns to analyse data by generating algorithms that cannot be predicted and that are difficult, or impossible, to comprehend. This introduces an unknown and perhaps unaccountable process between a person’s thoughts and the technology that is acting on their behalf.
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Maslen is already helping to shape BCI-device regulation. She is in discussion with the European Commission about regulations it will implement in 2020 that cover non-invasive brain-modulating devices that are sold straight to consumers. [emphases mine; Note: There is a Canadian company selling this type of product, MUSE] Maslen became interested in the safety of these devices, which were covered by only cursory safety regulations. Although such devices are simple, they pass electrical currents through people’s scalps to modulate brain activity. Maslen found reports of them causing burns, headaches and visual disturbances. She also says clinical studies have shown that, although non-invasive electrical stimulation of the brain can enhance certain cognitive abilities, this can come at the cost of deficits in other aspects of cognition.
Regarding my note about MUSE, the company is InteraXon and its product is MUSE.They advertise the product as “Brain Sensing Headbands That Improve Your Meditation Practice.” The company website and the product seem to be one entity, Choose Muse. The company’s product has been used in some serious research papers they can be found here. I did not see any research papers concerning safety issues.
… He [Gilbert] is now preparing a follow-up report on Patient 6. The company that implanted the device in her brain to help free her from seizures went bankrupt. The device had to be removed.
… Patient 6 cried as she told Gilbert about losing the device. … “I lost myself,” she said.
“It was more than a device,” Gilbert says. “The company owned the existence of this new person.”
It’s easy to forget that in all the excitement over technologies ‘making our lives better’ that there can be a dark side or two. Some of the points brought forth in the articles by Wolbring, Underwood, and Drew confirmed my uneasiness as reasonable and gave me some specific examples of how these technologies raise new issues or old issues in new ways.
What I find interesting is that no one is using the term ‘cyborg’, which would seem quite applicable.There is an April 20, 2012 posting here titled ‘My mother is a cyborg‘ where I noted that by at lease one definition people with joint replacements, pacemakers, etc. are considered cyborgs. In short, cyborgs or technology integrated into bodies have been amongst us for quite some time.
Interestingly, no one seems to care much when insects are turned into cyborgs (can’t remember who pointed this out) but it is a popular area of research especially for military applications and search and rescue applications.
I’ve sometimes used the term ‘machine/flesh’ and or ‘augmentation’ as a description of technologies integrated with bodies, human or otherwise. You can find lots on the topic here however I’ve tagged or categorized it.
Amongst other pieces you can find here, there’s the August 8, 2016 posting, ‘Technology, athletics, and the ‘new’ human‘ featuring Oscar Pistorius when he was still best known as the ‘blade runner’ and a remarkably successful paralympic athlete. It’s about his efforts to compete against able-bodied athletes at the London Olympic Games in 2012. It is fascinating to read about technology and elite athletes of any kind as they are often the first to try out ‘enhancements’.
Gregor Wolbring has a number of essays on The Conversation looking at Paralympic athletes and their pursuit of enhancements and how all of this is affecting our notions of abilities and disabilities. By extension, one has to assume that ‘abled’ athletes are also affected with the trickle-down effect on the rest of us.
Regardless of where we start the investigation, there is a sameness to the participants in neuroethics discussions with a few experts and commercial interests deciding on how the rest of us (however you define ‘us’ as per Gregor Wolbring’s essay) will live.
This paucity of perspectives is something I was getting at in my COVID-19 editorial for the Canadian Science Policy Centre. My thesis being that we need a range of ideas and insights that cannot be culled from small groups of people who’ve trained and read the same materials or entrepreneurs who too often seem to put profit over thoughtful implementations of new technologies. (See the PDF May 2020 edition [you’ll find me under Policy Development]) or see my May 15, 2020 posting here (with all the sources listed.)
As for this new research at Stanford, it’s exciting news, which raises questions, as it offers the hope of independent movement for people diagnosed as tetraplegic (sometimes known as quadriplegic.)
A February 4, 2020 news item on Nanowerk announces research that makes it possible for kidneys to remove nanoparticles after they’ve been used in therapeutic remedies (Note: A link has been removed),
In the past decade nanomedicine has contributed to better detection and treatment of cancer. Nanoparticles are several 100 times smaller than the smallest grain of sand and can therefore easily travel in the blood stream to reach the tumor.
However, they are still too big to be removed by the kidneys. Since several doses of nanoparticles are necessary to treat a tumor, over time the nanoparticles can accumulate in the kidney and cause irreversible damage.
In a study published in the scientific journal Biomaterials (“Renal clearance of polymeric nanoparticles by mimicry of glycan surface of Viruses”), materials scientists at the University of Freiburg [Germany] led by Prof. Dr. Prasad Shastri from the Institute of Macromolecular Chemistry now present a natural solution to this problem: they built nanoparticles with the carbohydrate polysaccharides, which led to the excretion of the particles.
In nature viruses such as the herpes simplex virus-1 and the cytomegalovirus, which are able to pass through the kidney filtration apparatus despite their large size compared to nanoparticles. Shastri and his team identified that both viruses presents sugar molecules on their surface. Inspired by this observation, the scientists engineered nanoparticles containing polysaccharides. These carbohydrates are frequently found in the human tissue environment. Using a real-time imaging technique, which they have established in their laboratory, the team investigated in a mouse model the fate of these nanoparticles. They observed that the polysaccharide-enriched nanoparticles readily pass through the kidney and are excreted with the urine within a few hours after intravenous administration. The decisive factor for the researchers was that the nanoparticles continued to act as intended and were still able to target tumors.
“The ability to combine tumor accumulation and kidney clearance in the same nanoparticle represents a tipping point in ensuring that nanomedicines can be safely administered” says Shastri. “Our nature-inspired approach enabled us to trick the kidney environment to let nanoparticles pass through” adds Dr. Melika Sarem who was a co-author of the study.
Prasad Shastri is Professor of Biofunctional Macromolecular Chemistry at the Institute for Macromolecular Chemistry and Professor of Cell Signalling Environments in the Excellence Cluster BIOSS Centre for Biological Signalling Studies and at the University of Freiburg.
Here’s a link to and a citation for the paper,
Renal clearance of polymeric nanoparticles by mimicry of glycan surface of viruses by Pradeep P.Wyss, Surya P.Lamichhane, Ahmed Abed, Daniel Vonwil, Oliver Kretz, Tobias B. Huber, Melika Sarema, V. Prasad Shastri. Biomaterials Volume 230, February 2020, 119643 DOI: https://doi.org/10.1016/j.biomaterials.2019.119643 First published online November 23, 2019
The power of the metaphor/analogy is demonstrated in a Sept. 24, 2013 news item on ScienceDaily where they’ve mentioned insects in the context of anti-adhesion—the opposite of how insects are usually referenced, i.e., how well they stick to surfaces and the search for better adhesives. Or you could put it down to lazy reading on my part as it took me a minute or so to make sense of what I was reading (from the news item),
Beetles, cockroaches, and ants will have a harder time walking up the sides of buildings or air conditioners in the future — thanks to the bio-inspired, anti-adhesive surfaces Prof. Dr. Thomas Speck, Dr. Bettina Prüm, and Dr. Holger Bohn are developing together with the Plant Biomechanics Group of the University of Freiburg. The team studied plant surfaces in order to determine what influence cell form and microstructure as well as surface chemistry exert on the adhesion behavior of insects.
The researchers conducted adhesion experiments in which Colorado potato beetles walked across differently structured plant surfaces as well as replicas made of synthetic resins. The team used a highly sensitive sensor to measure the traction forces of the beetles on various surfaces. They discovered that wavy or strongly curved cells can increase the adhesive powers of beetles, whereas microstructures composed of wax crystals or cuticular folds reduce them. The latter are tiny folds in the cuticle, a protective layer on the surface of the leaf resembling polyester. The beetles had the hardest time walking on surfaces with cuticular folds with a height and width of approximately 0.5 micrometers and a spacing of between 0.5 and 1.5 micrometers. “That is the perfect anti-adhesion surface. The insects slip off of it much easier than off glass,” says project director Thomas Speck. The cuticular folds reduce the contact area between the adhesive hairs on the beetles’ legs and the plant surface. Unlike on more coarsely structured surfaces, the beetle can’t dig its feet firmly into the cuticular folds. Thus, the microstructure of the surface has a stronger effect on the adhesion of the beetle than the cell form.
The team also took contact angle measurements to investigate the wettability of the various surfaces. The researchers used hydrophobic and hydrophilic artificial moldings of the microstructured plant surfaces in order to study the influence of the surface chemistry on surface wettability and the beetles’ walking behavior. Much like wax crystals, cuticular folds are very good at repelling water. In contrast to the wettability, which depends on both the microstructure and the surface chemistry, the walking behavior of the beetles is not influenced by the surface chemistry. This means that the beetle’s adhesive power depends solely on the physical microstructure of the surface.
Here’s a link to and a citation for the researchers’ paper,
