03 Apr 2017
Rubbery, multifunctional fibers could be used to study spinal cord neurons and potentially restore function.
Implantable fibers have been an enormous boon to brain research, allowing scientists to stimulate specific targets in the brain and monitor electrical responses. But similar studies in the nerves of the spinal cord, which might ultimately lead to treatments to alleviate spinal cord injuries, have been more difficult to carry out.
That’s because the spine flexes and stretches as the body moves, and the relatively stiff, brittle fibers used today could damage the delicate spinal cord tissue.
Now, researchers have developed a rubber-like fiber that can flex and stretch while simultaneously delivering both optical impulses, for optoelectronic stimulation, and electrical connections, for stimulation and monitoring. The new fibers are described in a paper in the journal Science Advances, by MIT graduate students Chi (Alice) Lu and Seongjun Park, Professor Polina Anikeeva, and eight others at MIT, the University of Washington, and Oxford University.
“I wanted to create a multimodal interface with mechanical properties compatible with tissues, for neural stimulation and recording,” as a tool for better understanding spinal cord functions, says Lu. But it was essential for the device to be stretchable, because “the spinal cord is not only bending but also stretching during movement.” The obvious choice would be some kind of elastomer, a rubber-like compound, but most of these materials are not adaptable to the process of fiber drawing, which turns a relatively large bundle of materials into a thread that can be narrower than a hair.
The spinal cord “undergoes stretches of about 12 percent during normal movement,” says Anikeeva, who is the Class of 1942 Career Development Professor in the Department of Materials Science and Engineering. “You don’t even need to get into a ‘downward dog’ [yoga position] to have such changes.” So finding a material that can match that degree of stretchiness could potentially make a big difference to research. “The goal was to mimic the stretchiness and softness and flexibility of the spinal cord,” she says. “You can match the stretchiness with a rubber. But drawing rubber is difficult — most of them just melt,” she says.
“Eventually, we’d like to be able to use something like this to combat spinal cord injury. But first, we have to have biocompatibility and to be able to withstand the stresses in the spinal cord without causing any damage,” she says.
The fibers are not only stretchable but also very flexible. “They’re so floppy, you could use them to do sutures, and do light delivery at the same time,” professor Polina Anikeeva says. (Video: Chi (Alice) Lu and Seongjun Park)
The team combined a newly developed transparent elastomer, which could act as a waveguide for optical signals, and a coating formed of a mesh of silver nanowires, producing a conductive layer for the electrical signals. To process the transparent elastomer, the material was embedded in a polymer cladding that enabled it to be drawn into a fiber that proved to be highly stretchable as well as flexible, Lu says. The cladding is dissolved away after the drawing process.
After the entire fabrication process, what’s left is the transparent fiber with electrically conductive, stretchy nanowire coatings. “It’s really just a piece of rubber, but conductive,” Anikeeva says. The fiber can stretch by at least 20 to 30 percent without affecting its properties, she says.
The fibers are not only stretchable but also very flexible. “They’re so floppy, you could use them to do sutures and deliver light at the same time,” she says.
“We’re the first to develop something that enables simultaneous electrical recording and optical stimulation in the spinal cords of freely moving mice,” Lu says. “So we hope our work opens up new avenues for neuroscience research.” Scientists doing research on spinal cord injuries or disease usually must use larger animals in their studies, because the larger nerve fibers can withstand the more rigid wires used for stimulus and recording. While mice are generally much easier to study and available in many genetically modified strains, there was previously no technology that allowed them to be used for this type of research, she says.
“There are many different types of cells in the spinal cord, and we don’t know how the different types respond to recovery, or lack of recovery, after an injury,” she says. These new fibers, the researchers hope, could help to fill in some of those blanks.
The team included Alexander Derry, Chong Hou, Siyuan Rao, Jeewoo Kang, and professor Yoel Fink at MIT; Tom Richner and professor Chet Mortiz at the University of Washington; and Imogen Brown at Oxford University. The research was supported by the National Science Foundation, the National Institute of Neurological Disorders and Stroke, the U.S. Army Research Laboratory, and the U.S. Army Research Office through the Institute for Soldier Nanotechnologies at MIT.
14 Feb 2017
Creating a Life-Saving, Blood-Repellent Super Material – Revolutionizing Medical Implants: Colorado State University
Goodbye Rejection – Implanted medical devices like stents, catheters, and titanium rods are essential, life-saving tools for patients around the world. Still, having a foreign object in the human body does pose its own risks – chiefly, having the body reject the object or increasing the risk of dangerous blood clots. A new collaboration between two distinct scientific disciplines is working toward making those risks a concern of the past.
Biomedical engineers and materials scientists from Colorado State University (CSU) ….
Florida State University College of Engineering Assistant Professor Shangchao Lin has published a new paper in the journal ACS Nano that predicts how an organic-inorganic hybrid material called organometal halide perovskites could be more mechanically flexible than existing silicon and other inorganic materials used for solar cells, thermoelectric devices and light-emitting diodes.
What if every vehicle, home appliance, heating system and light switch were connected to the Internet? Today, that’s not such a stretch of the imagination.
Modern cars, for instance, already have hundreds of sensors and multiple computers connected over an internal network. And that’s just one example of the 6.4 billion connected “things” in use worldwide this year, according to research by Gartner Inc. DHL and Cisco Systems offer even higher estimates—their 2015 Trend Report sets the current number of connected devices at about 15 billion, amidst industry expectations that the tally will increase to 50 billion by 2020.
Author: Tilda Barliya PhD
Peripheral nerve lacerations are common injuries and often cause long lasting disability (1a) due to pain, paralyzed muscles and loss of adequate sensory feedback from the nerve receptors in the target organs such as skin, joints and muscles (1b).
Nerve injuries are common and typically affect young adults with the majority of injuries occur from trauma or complication of surgery. Traumatic injuries can occur due to stretch, crush, laceration (sharps or bone fragments), and ischemia, and are more frequent in wartime, i.e., blast exposure. Domestic or occupational accidents with glass, knifes of machinery may also occur.
Statistics show that peripheral nervous system (PNS) injuries were 87% from trauma and 12% due to surgery (one-third tumor related, two-thirds non– tumor related). Nerve injuries occurred 81% of the time in theupper extremities and 11% in the lower extremities, with the balance in other locations (4).
Injury to the PNS can range from severe, leading to major loss of function or intractable neuropathic pain, to mild, with some sensory and/or motor deficits affecting quality of life.
Functional recovery after nerve injury involves a complex series of steps, each of which may delay or impair the regenerative process. In cases involving any degree of nerve injury, it is useful initially to categorize these regenerative steps anatomically on a gross level. The sequence of regeneration may be divided into anatomical zones (4):
- the neuronal cell body
- the segment between the cell body and the injury site
- the injury site itself
- the distal segment between the injury site and the end organ
- the end organ itself
A delay in regeneration or unsuccessful regeneration may be attributed to pathological changes that impede normal reparative processes at one or more of these zones.
Repairing nerve defects with large gaps remains one of the most operative challenges for surgeons. Incomplete recovery from peripheral nerve injuries can produce a diversity of negative outcomes, including numbness, impairment of sensory or motor function, possibility of developing chronic pain, and devastating permanent disability.
In the past few years several techniques have been used to try and repair nerve defects and include:
- Nerve autograph
- Biological or polymeric nerve conduits (hollow nerve guidance conduits)
For example, When a direct repair of the two nerve ends is not possible, synthetic or biological nerve conduits are typically used for small nerve gaps of 1 cm or less. For extensive nerve damage over a few centimeters in length, the nerve autograft is the “gold standard” technique. The biggest challenges, however, are the limited number and length of available donor nerves, the additional surgery associated with donor site morbidity, and the few effective nerve graft alternatives.
Degeneration of the axonal segment in the distal nerve is an inevitable consequence of disconnection, yet the distal nerve support structure as well as the final target must maintain efficacy to guide and facilitate appropriate axonal regeneration. There is currently no clinical practice targeted at maintaining fidelity of the distal pathway/target, and only a small number of researchers are investigating ways to preserve the distal nerve segment, such as the use of electrical stimulation or localized drug delivery. Thus development of tissue-engineered nerve graft may be a better matched alternative (6,7).
The guidance conduit serves several important roles for nerve regeneration such as: a) directing axonal sprouting from the regenerating nerve b) protecting the regenerating nerve by restricting the infiltration of fibrous tissue c) providing a pathway for diffusion of neurotropic and neurotophic factors
Early guidance conduits were primarily made of silicone due to its stability under physiological conditions, biocompatibility, flexibility as well as ease of processing into tubular structures. Although silicone conduits have proven reasonably successful as conduits for small gap lengths in animal models (<5 mm). The non-biodegradability of silicone conduits has limited its application as a strategy for long-term repair and recovery. Tubes also eventually become encapsulated with fibrous tissue, which leads to nerve compression, requiring additional surgical intervention to remove the tube.Another limiting factor with inert guidance conduits is that they provide little or no nerve regeneration for gap lengths over 10 mm in the PNS unless exogenous growth factors are used (6,7).
In animal studies, biodegradable nerve guidance conduits have provided a feasible alternative, preventing neuroma formation and infiltration of fibrous tissue. Biodegradable conduits have been fabricated from natural or synthetic materials such as collagen, chitosan and poly-L-lactic acid.
Nanostructured Scaffolds for Neural Tissue Engineering: Fabrication and Design
At the micro- and nanoscale, cells of the CNS/PNS reside within functional microenvironments consisting of physical structures including pores, ridges, and fibers that make up the extracellular matrix (ECM) and plasma membrane cell surfaces of closely apposed neighboring cells. Cell-cell and cell-matrix interactions contribute to the formation and function of this architecture, dictating signaling and maintenance roles in the adult tissue, based on a complex synergy between biophysical (e.g. contact-mediated signaling, synapse control), and biochemical factors (e.g. nutrient support and inflammatory protection). Neural tissue engineering scaffolds are aimed toward recapitulating some of the 3D biological signaling that is known to be involved in the maintenance of the PNS and CNS and to facilitate proliferation, migration and potentially differentiation during tissue repair.
Nanotechnology and tissue engineering are based on two main approaches:
- Electrospinning (top-down) – involves the production of a polymer filament using an electrostatic force. Electrospinning is a versatile technique that enables production of polymer fibers with diameters ranging from a few microns to tens of nanometers.
- Molecular self-assembly of peptides (bottom-up) – Molecular self-assembly is mediated by weak, non-covalent bonds, such as van der Waals forces, hydrogen bonds, ionic bonds, and hydrophobic interactions. Although these bonds are relatively weak, collectively they play a major role in the conformation of biological molecules found in nature.
Pfister et al (6) very nicely summarized the various polymeric fibers been used to achieve the goal of nerve regeneration, even in humans. These material include a wide array of polymers from silica to PLGA/PEG and Diblock copolypeptides.
Many of these approaches also enlist many trophic factors that have been investigated in nerve conduits
Currently there are three general biomaterial approaches for local factor delivery:
- Incorporation of factors into a conduit filler such as a hydrogel
- Designing a drug release system from the conduit biomaterial such as microspheres
- Immobilizing factors on the scaffold that are sensed in place or liberated upon matrix degradation.
Maeda et al had a creative approach to bridge larger gaps by using the combination of nerve grafts and open conduits in an alternating “stepping stone” assembly, which may perform better than an empty conduit alone (8).
Peripheral nerve repair is a growing field with substantial progress being made in more effective repairs. Nanotechnology and biomedical engineering have made significant contributions; from surgical instrumentation to the development of tissue engineered grafting substitutes. However, to date the field of neural tissue engineering has not progressed much past the conduit bridging of small gaps and has not come close to matching the autograf. Much more studies are needed to understand the cell behaviour that can promote cell survival, neurite outgrowth, appropriate re-innervation and consequently the functional recovery post PNS/CNS injuries. This is since understanding of the cellular response to the combination of these external cues within 3D architectures is limited at this stage.
1a. Jaquet JB, Luijsterburg AJ, Kalmijn S, Kuypers PD, Hofman A, Hovius SE. Median, ulnar, and combined median-ulnar nerve injuries:functional outcome and return to productivity. J Trauma 2001 51: 687-692.http://www.ncbi.nlm.nih.gov/pubmed/11586160
1b. Lundborg G, Rosen B. Hand function after nerve repair. Acta Physiol (Oxf) 2007 189: 207-217. http://www.ncbi.nlm.nih.gov/pubmed/17250571
1. Chang WC., Kliot M and Stretavan DW. Microtechnology and Nanotechnology in Nerve Repair. Neurological Research 2008; vol 30: 1053-1062. http://vision.ucsf.edu/sretavan/sretavanpdfs/2008b-Chang%20&%20Sretavan.pdf
2. Biazar E., Khorasani MT and Zaeifi D. Nanotechnology for peripheral nerve regeneration. Int. J. Nano. Dim. 2010 1(1): 1-23. http://www.ijnd.ir/doc/2010-v1-i1/2010-V1-I1-1.pdf
3. Albert Aguayo. Nerve regeneration revisited. Nature Reviews Neuroscience 7, 601 (August 2006).
4. Burnett MG and Zager EL. Pathophysiology of Peripheral Nerve Injury: A Brief Review. Neurosurg Focus. 2004;16(5) .
5. Dag Welin. Neuroprotection and axonal regeneration after peripheral nerve injury. MEDICAL DISSERTATIONS
Welin, D., Novikova, L.N., Wiberg, M., Kellerth, J-O. and Novikov, L.N. Survival and regeneration of cutaneous and muscular afferent neurons after peripheral nerve injury in adult rats. Experimental Brain Research, 186, 315-323, 2008.
6. Pfister BJ., Gordon T., Loverde JR., Kochar AS., Mackinnon SE and Cullen Dk. Biomedical Engineering Strategies for Peripheral Nerve Repair: Surgical Applications, State of the Art, and Future Challenges. Critical Reviews™ in Biomedical Engineering 2011, 39(2):81–124.http://www.med.upenn.edu/cullenlab/user_documents/2011Pfisteretal-PNIReviewArticleCritRevBME.pdf
7. Zhou K, Nisbet D, Thouas G, Bernard C and Forsythe J. Bio-nanotechnology Approaches to Neural Tissue Engineering. Intechopen. Com. http://cdn.intechopen.com/pdfs/9811/InTech-Bio_nanotechnology_approaches_to_neural_tissue_engineering.pdf
8. Maeda T, Mackinnon SE, Best TJ, Evans PJ, Hunter DA, Midha RT. Regeneration across ’stepping-stone’ nerve grafts. Brain Res. 1993;618(2):196–202. http://www.ncbi.nlm.nih.gov/pubmed/?term=Maeda+T+and+regeneration+across+stepping+stone
Graphene is a two-dimensional form of carbon, and successful demonstrations have been carried out by researchers to prove the possibility of interfacing graphene with nerve cells, or neurons, without affecting their integrity.
The demonstrations could help to develop graphene-based electrodes, which could be safely implanted into the brain. This study shows potential in restoring the sensory functions for individuals with Parkinson’s disease, epilepsy, amputees or paralyzed patients.
The Cambridge Graphene Centre and the University of Trieste in Italy together worked on this research, which was published in ACS Nano.
Other research teams have earlier demonstrated the possibility of using treated graphene to work with neurons. However very low signal to noise ratio was obtained from this interface. In this work, techniques were developed that allow the use of untreated graphene, and as a result they were able to retain the electrical conductivity of the material. This enables the graphene to function as a better electrode.
For the first time we interfaced graphene to neurons directly. We then tested the ability of neurons to generate electrical signals known to represent brain activities, and found that the neurons retained their neuronal signaling properties unaltered. This is the first functional study of neuronal synaptic activity using uncoated graphene based materials.
Professor Laura Ballerini, University of Trieste
It is possible to control some of the functions of the brain, by directly interfacing between the brain and the outside environment. For instance, it is possible to retrieve the sensory organs by evaluating the electrical impulses of the brain. This could help to control an amputee patient’s robotic arms or basic processes for paralyzed individuals, such as helping them with their speech and movement of objects surrounding them. It is also possible to control motor disorders like Parkinson’s disease or epilepsy when these electrical impulses are interfered with.
To make this possible, scientists have created electrodes that can be inserted deep into the human brain. These electrodes come into direct contact with the neurons and then send out electrical signals from the body to decode their meaning.
The issue that exists in the interface between neurons and electrodes is that the electrodes are not only expected to be extremely sensitive to electrical impulses, but they are also expected to be firm in the body without making changes in the tissue that is measured.
Often modern electrodes used for the tungsten-based or silicon-based interface suffer from complete or partial loss of signal over time. This occurs when scar tissues are created when the electrode is inserted, stopping the movement of the electrode with the natural movements of the brain due to its firm nature.
These issues can be solved using graphene due to its efficient stability, flexibility, conductivity, and biocompatibility within the body.
The researchers carried out experiments in the brain cell cultures of rats and concluded that interfacing with neurons was efficient in the case of untreated graphene electrodes. Based on the studies conducted on the neurons with electron microscopy and immunofluorescence, the researchers highlighted that the neurons continued to be healthy and transmitted normal electric impulses. Negative reactions that cause damage to the scar tissue were also not seen.
The research team considered this to be the first step in using pristine graphene-based materials instead of electrodes for a neuro-interface. The team plan to examine how different types of graphene, ranging from multiple layers to monolayers, are capable of affecting neurons. The researchers also plan to analyze whether changes made to the material properties of graphene can alter the neuronal excitability and synapses in unique ways.
Hopefully this will pave the way for better deep brain implants to both harness and control the brain, with higher sensitivity and fewer unwanted side effects.
Professor Laura Ballerini, University of Trieste
“We are currently involved in frontline research in graphene technology towards biomedical applications,” said Professor Maurizio Prato from the University of Trieste. “In this scenario, the development and translation in neurology of graphene-based high-performance biodevices requires the exploration of the interactions between graphene nano- and micro-sheets with the sophisticated signaling machinery of nerve cells. Our work is only a first step in that direction.”
These initial results show how we are just scratching the tip of an iceberg when it comes to the potential of graphene and related materials in bio-applications and medicine. The expertise developed at the Cambridge Graphene Centre allows us to produce large quantities of pristine material in solution, and this study proves the compatibility of our process with neuro-interfaces.
Professor Andrea Ferrari, Director of the Cambridge Graphene Centre
The research was financially supported by the European initiative, Graphene Flagship.
The Fourth Industrial Revolution is being driven by a staggering range of new technologies that are blurring the boundaries between people, the internet and the physical world. It’s a convergence of the digital, physical and biological spheres. It’s a transformation in the way we live, work and relate to one another in the coming years, affecting entire industries and economies, and even challenging our notion of what it means to be human.
So what exactly are these technologies, and what do they mean for us?
Computing capabilities, storage and access
Between 1985 and 1989, the Cray-2 was the world’s fastest computer. It was roughly the size of a washing machine. Today, a smart watch has twice its capabilities.
As mobile devices become increasingly sophisticated, experts say it won’t be long before we are all carrying “supercomputers” in our pockets. Meanwhile, the cost of data storage continues to fall, making it possible keep expanding our digital footprints.
Today, 43% of the world’s population are connected to the internet, mostly in developed countries. The United Nations has set the goal of connecting all the world’s inhabitants to affordable internet by 2020. This will increase access to information, education and global marketplaces, which will empower many people to improve their living conditions and escape poverty. Imagine a world where everyone is connected by mobile devices with unprecedented processing power and storage capacity!
If we can achieving the goal of universal internet access and overcome other barriers such as digital illiteracy, everybody could have access to knowledge, and all the possibilities this brings.
Each time you run a Google search, scan your passport, make an online purchase or tweet, you are leaving a data trail behind that can be analysed and monetized.
Thanks to supercomputers and algorithms, we can make sense of massive amounts of data in real time. Computers are already making decisions based on this information, and in less than 10 years computer processors are expected to reach the processing power of the human brain. This means there’s a good chance your job could be done by computers in the coming decades. Two Oxford researchers, Carl Bendikt Frey and Michael A Osborne, estimated that 47% of American jobs are at high risk of automation.
A survey done by the Global Agenda Council on the Future of Software & Society shows people expect artificial intelligence machines to be part of a company’s board of directors by 2026.
Analyzing medical data collated from different populations and demographics enables researchers to understand patterns and connections in diseases and identify which conditions improve the effectiveness of certain treatments and which don’t.
Big data will help to reduce costs and inefficiencies in healthcare systems, improve access and quality of care, and make medicine more personalized and precise.
In the future, we will all have very detailed digital medical profiles … including information that we’d rather keep private. Digitization is empowering people to look after their own health. Think of apps that track how much you eat, sleep and exercise, and being able to ask a doctor a question by simply tapping it into your smartphone.
In addition, advances in technologies such as CRISPR/Cas9, which unlike other gene-editing tools, is cheap, quick and easy to use, could also have a transformative effect on health, with the potential to treat genetic defects and eradicate diseases.
The digitization of matter
3D printers will create not only cars, houses and other objects, but also human tissue, bones and custom prosthetics. Patients would not have to die waiting for organ donations if hospitals could bioprint them. In fact, we may have already reached this stage: in 2014, doctors in China gave a boy a 3D-printed spine implant, according to the journal Popular Science.
The 3D printing market for healthcare is predicted to reach some $4.04 billion by 2018. According to a survey by the Global Agenda Council on the Future of Software and Society, most people expect that the first 3D printed liver will happen by 2025. The survey also reveals that most people expect the first 3D printed car will be in production by 2022.
Three-dimensional printing, which brings together computational design, manufacturing, materials engineering and synthetic biology, reduces the gap between makers and users and removes the limitations of mass production. Consumers can already design personalized products online, and will soon be able to simply press “print” instead of waiting for a delivery.
The Internet of Things (IOT)
Within the next decade, it is expected that more than a trillion sensors will be connected to the internet. If almost everything is connected, it will transform how we do business and help us manage resources more efficiently and sustainably. Connected sensors will be able to share information from their environment and organize themselves to make our lives easier and safer. For example, self-driving vehicles could “communicate” with one another, preventing accidents.
By 2020 around 22% of the world’s cars will be connected to the internet (290 million vehicles), and by 2024, more than half of home internet traffic will be used by appliances and devices.
Home automation is also happening fast. We can control our lights, heating, air conditioning and security systems remotely, but how much longer will it be before sensors are able to detect crumbs under the table and tell our automated vacuum cleaners to tidy up? The internet of things will create huge amounts of data, raising concerns over who will own it and how it will be stored. And what about the possibility that your home or car could be hacked?
Only a tiny fraction of the world’s GDP (around 0.025%) is currently held on blockchain, the shared database technology where transactions in digital currencies such as the Bitcoin are made. But this could be about to change, as banks, insurers and companies race to work out how they can use the technology to cut costs.
A blockchain is essentially a network of computers that must all approve a transaction before it can be verified and recorded. Using cryptography to keep transactions secure, the technology provides a decentralized digital ledger that anyone on the network can see.
Before blockchain, we relied on trusted institution such as a bank to act as a middleman. Now the blockchain can act as that trusted authority on every type of transaction involving value including money, goods and property. The uses of blockchain technology are endless. Some expect that in less than 10 years it will be used to collect taxes. It will make it easier for immigrants to send money back to countries where access to financial institutions is limited.
And financial fraud will be significantly reduced, as every transaction will be recorded and distributed on a public ledger, which will be accessible by anyone who has an internet connection.
Source: Financial Times
Technology is getting increasingly personal. Computers are moving from our desks, to our laps, to our pockets and soon they will be integrated into our clothing. By 2025, 10% of people are expected to be wearing clothes connected to the internet and the first implantable mobile phone is expected to be sold.
Implantable and wearable devices such as sports shirts that provide real-time workout data by measuring sweat output, heart rate and breathing intensity are changing our understanding of what it means to be online and blurring the lines between the physical and digital worlds.
The potential benefits are great, but so are the challenges. These devices can provide immediate information about our health and about what we see, or help locate missing children. Being able to control devices with our brains would enable disabled people to engage fully with the world. There would be exciting possibilities for learning and new experiences.
But how would it affect our personal privacy, data security and our personal relationships? In the future, will it ever be possible to be offline anymore?
More on the Fourth Industrial Revolution
What is the Fourth Industrial Revolution?
Is technological change creating a new global economy?
Health and the Fourth Industrial Revolution
Proponents of “bigger is better” may want to think again, particularly when it comes to nanotechnology. That’s because advancements in nanotechnology could also mean advancements in the medical devices market.
Nanotechnology is proving to be a viable avenue for the medical technology sector, which, as Nanotechnology Now explains, is “having a massive effect on how doctors and scientists treat patients and gain further insight into the human body and disease prevention.”
Medical nanotechnology for heart disease
One disease prevention measure being researched is heart attack detection. Researchers at the San Diego-based Scripps Health Institute are looking at injecting nanosensor chips into the bloodstreams of test subjects at high risk of heart attacks. According to Nanotechnology Now, the aim of the research is to “create a chip that could notice the chemical changes that precede a heart attack,” alerting the subject to see immediate medical attention.
Medical nanotechnology for fertility
One of the main drivers of infertility is healthy sperm that do not swim well. To assist with infertility, women can generally turn to several forms of assisted insemination, from artificial insemination to in vitro fertilization. But all that may be set to change — Germany-based Oliver Schmidt and his team at IFW are working on a new type of nanotechnology that aims to increase sperm mobility: the spermbot.
Source: American Chemical Society
The technology involves building tiny metal helices large enough to fit around the tail of the sperm. Using a rotating magnetic field, the sperm can be directed to an egg for potential fertilization, and then released. Though more research needs to be done before the technique is ready for clinical tests,Nanowerk states that the team’s initial demonstration shows a lot of promise.
Medical nanotechnology for cancer
Treating cancer is difficult because until recently, there was no treatment that could target individual cancerous cells without destroying the surrounding healthy cells. Now, however, researchers at Israel’s Bar-Ilan University have confirmed that nanobots capable of fighting cancerous cells have become a reality. The nanobots, which measure between 25 and 35 nanometers, can barely be seen by the naked eye.
The nanobots are made from DNA, “specifically a single strand of DNA folded into a desired shape,” 3Tags notes, adding that the nanobots have been programmed to turn “on” and “off” so that they can either bypass healthy cells without causing damage or target cancerous cells.
The first human trial later is expected to move forward later this year. Though the patient, a person with late-stage leukemia, is expected to die, Professor Ido Bachelet believes that “based on previous animal trials, the nanobots can remove the cancer in the span of a month.” Bachelet said, “[i]f the trial goes well, we could see nanotechnology hit the public in one-to-five years.”
Nanotechnology sector expected to grow
Based on the information above, it’s clear that nanotechnology plays a big role in the life sciences sector. In fact, a report from BCC Research highlights that in 2014, the nanomedicine market was valued at $248.3 billion, with a projected compound annual growth rate of 16.3 percent through to 2019. That means by 2019 the nanomedicine market may be valued in the range of $528 billion.
Until then, investors should expect to see more advancements in research for medical nanotechnology.
An Imperial College London team is pioneering nanoscale robotic surgical instruments which can, among other uses, better target cancer cells with chemotherapy drugs.
When Chinese president Xi Jinping visited Britain last October, one of the more unusual gifts he received was one he couldn’t actually see – a model of the Great Wall of China which was the same width as a human hair.
Researchers at Imperial College had used advanced 3D printing techniques to make the model. But the more practical use of the technology is for the development of advanced surgical instruments. The detail of these precision surgery instruments cannot be seen by the human eye, but they are expected to replace the large robotic instruments used in operating theatres at present.
At the cutting edge of work being carried out at the Hamlyn Centre in Imperial College, a lab which develops technologies for use in healthcare, is a clasping hand which is little more than half the breadth of a hair. As well as being used in surgery, the device could be applied to the more efficient delivery of cancer drugs.
According to the centre’s director, Prof Guang-Zhong Yang, the new smart surgical instruments, effectively handheld robots, will improve efficiency and cut costs. At present, robots in operating theatres are large imposing machines which can be operated by surgeons, be they present or remote. The new smaller handheld instruments allow a surgeon more room to work. Yang explains that instead of having a large robot towering over the patient, surgeons instead use handheld robotic instruments allowing them to operate as normal.
In the Hamlyn Centre on the Kensington campus of Imperial College lies a room which Yang refers to as “the museum”. Inside there are past and present generations of robots used for general surgery and procedures used in urology and gynaecology.
The robot’s arms make incisions and relay camera images to the surgeon who controls them. There are about 3,000 such machines in use around the world, each with a multimillion-pound price tag.
Across the corridor from “the museum” sits the lab where Yang’s team is developing the new handheld devices, the polar opposite of the large machines utilised at present. Using 3D printing at nanoscale, they have developed a clasping hand that fits on top of a minute piece of fibre which can be used for precise drug delivery and surgery.
The device measures just 60 microns across – a human hair is 100 microns wide, a red blood cell about 10 microns. It is produced by using a technique called two photon polymerisation, where a controlled point of pulsed laser is used to join together molecules to solidify a light-sensitive material.
This tiny device enables surgeons to carry out procedures at human cell level, says Yang. “At the very tip of the fibre we are able to put very small manipulators,” he says. “At the moment, for surgical procedures we still need to make incisions for the instruments but in the future we will probably just use a small needle.”
Other uses include the better targeted delivery of drugs for cancer care, says Yang. Chemotherapy drugs can affect cells in the body other than the cancer cells – causing tiredness and sickness – but the new implements will be able to carry tiny “payloads” of drugs for more precise delivery.
“Surgery is a different game altogether in the future. [It is] not about manipulating and stitching up tissue,” he says. “Our aim is … to do things with bare hands that you cannot do, to do things that are more accurate and more informative and then you do things that the other alternative techniques cannot do.”
Yang says he expects this new generation of surgical instruments to be in general use within a decade. Fibres with the manipulative hands on top will likely come in sterile packaging and be disposed of after one use. It is hoped the implements will be made available to a whole new group of surgeons, because they will be far cheaper than the multimillion-pound robots used today.
Yang makes it clear that the new smart instruments are not intended to replace surgeons but to let them continue to do what they do well and improve upon what they can’t.
Rather than having a very small minority of super-surgeons, there will be more doctors able to carry out procedures. Says Yang: “You improve the consistency, you improve the safety, you have more people able to do complex procedures and therefore the healthcare provision for everyone will be better.”
A 3D PRINTED FUTURE
It was more than 30 years ago when a method of manufacturing called stereolithography, now known as 3D printing, was discovered.
Chuck Hull, who was back then working for a company which used UV light to put thin layers of plastic veneers on tabletops and furniture, was frustrated that the production of small plastic parts for prototyping new product designs could take up to two months.
He developed a system in which light was shone into a vat of photopolymer – a material which changes from liquid to a plastic-like solid when light shines upon it – and traces the shape of one level of the object. Subsequent layers are then printed until it is complete. The technology used at Imperial College works in a similar manner, whereby a structure is built layer upon layer but at a minute scale.
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05 Oct 2015
|Source: University of Illinois College of Engineering|
A schematic of targeted drug delivery towards breast cancer is shown. Nanodiamonds are encapsulated within liposomes that are functionalized with targeting antibodies. Credit: Dr. Laura Moore (Prof. Dean Ho Group)
A trio of researchers, Dean Ho, with UCLA in the U.S., Chung-Huei Katherine Wang, with BRIM Biotechnology Inc., in Taipei and Edward Kai-Hua Chow with the National University of Singapore, has published a review in Science Advances, of the ways nanodiamonds are being used in cancer research and offer insights into the ways they may be used in the future.
As the research trio note, significant progress has been made over the past several decades in the development of nano-materials for use in treating cancer and other ailments. The central idea is to use very tiny particles to carry tumor fighting drugs to tumors (they are not as easily repelled as the larger varieties) thereby healing the patient. The list includes metallic particles, nanotubes, polymers and even lipids. More recently, scientists have been looking into using nanodiamonds as more is learned about the electrostatic capabilities of their facet surfaces when they carry chemicals in a biological system, the ways their inert core can be useful in certain applications and as a means to capitalize on their tunable surfaces.
The authors note that nanodiamonds used in medical applications fall into two main categories, detonation nanodiamonds (DNDs) and fluorescent nanodiamonds (FNDs) as part of highlighting the major ways that nanodiamonds are currently being used:
Imaging—both DNDs and FNDs, the researchers note are increasingly being eyed as a way to improve magnetic resonance imaging and more recently FNDs are also being seen as a way to track stem cells to learn more about their regenerative potential.
Drug Delivery—a lot of research is currently going on to learn more about which types of drugs adhere well to nanodiamond facets, most specifically those used in chemotherapy applications.
Biodistribution and Toxicity—similarly, a lot of research is being conducted to learn more about the ways nanodiamonds can be placed into a living organism (injection, consumption, though the skin, etc.) and whether there is a danger of toxicity.
The researchers note that another area of study involves using nanodiamonds as part of drug testing—if medications can be carried to specific sites, they note, there might be less side-effects.
Another benefit of using nanodiamonds, they note, is that despite being associated with precious gems, nanodiamonds would be quite cheap to procure and use because they can be obtained from mining waste.
Explore further: Tiny diamonds to boost treatment of chemoresistant leukemia
More information: Nanodiamonds: The intersection of nanotechnology, drug development, and personalized medicine, Science Advances 21 Aug 2015: Vol. 1, no. 7, e1500439. DOI: 10.1126/sciadv.1500439
The implementation of nanomedicine in cellular, preclinical, and clinical studies has led to exciting advances ranging from fundamental to translational, particularly in the field of cancer. Many of the current barriers in cancer treatment are being successfully addressed using nanotechnology-modified compounds. These barriers include drug resistance leading to suboptimal intratumoral retention, poor circulation times resulting in decreased efficacy, and off-target toxicity, among others.
The first clinical nanomedicine advances to overcome these issues were based on monotherapy, where small-molecule and nucleic acid delivery demonstrated substantial improvements over unmodified drug administration. Recent preclinical studies have shown that combination nanotherapies, composed of either multiple classes of nanomaterials or a single nanoplatform functionalized with several therapeutic agents, can image and treat tumors with improved efficacy over single-compound delivery. Among the many promising nanomaterials that are being developed, nanodiamonds have received increasing attention because of the unique chemical-mechanical properties on their faceted surfaces.
More recently, nanodiamond-based drug delivery has been included in the rational and systematic design of optimal therapeutic combinations using an implicitly de-risked drug development platform technology, termed Phenotypic Personalized Medicine–Drug Development (PPM-DD). The application of PPM-DD to rapidly identify globally optimized drug combinations successfully addressed a pervasive challenge confronting all aspects of drug development, both nano and non-nano. This review will examine various nanomaterials and the use of PPM-DD to optimize the efficacy and safety of current and future cancer treatment. How this platform can accelerate combinatorial nanomedicine and the broader pharmaceutical industry toward unprecedented clinical impact will also be discussed.
31 Aug 2015
Before Ibuprofen can relieve your headache, it has to dissolve in your bloodstream. The problem is Ibuprofen, in its native form, isn’t particularly soluble. Its rigid, crystalline structures — the molecules are lined up like soldiers at roll call — make it hard to dissolve in the bloodstream. To overcome this, manufacturers use chemical additives to increase the solubility of Ibuprofen and many other drugs, but those additives also increase cost and complexity.
The key to making drugs by themselves more soluble is not to give the molecular soldiers time to fall in to their crystalline structures, making the particle unstructured or amorphous.
Researchers from Harvard John A. Paulson School of Engineering and Applied Science (SEAS) have developed a new system that can produce stable, amorphous nanoparticles in large quantities that dissolve quickly.
But that’s not all. The system is so effective that it can produce amorphous nanoparticles from a wide range of materials, including for the first time, inorganic materials with a high propensity towards crystallization, such as table salt.
These unstructured, inorganic nanoparticles have different electronic, magnetic and optical properties from their crystalized counterparts, which could lead to applications in fields ranging from materials engineering to optics.
David A. Weitz, Mallinckrodt Professor of Physics and Applied Physics and an associate faculty member of the Wyss Institute for Biologically Inspired Engineering at Harvard, describes the research in a paper published today in Science.
“This is a surprisingly simple way to make amorphous nanoparticles from almost any material,” said Weitz. “It should allow us to quickly and easily explore the properties of these materials. In addition, it may provide a simple means to make many drugs much more useable.”
The technique involves first dissolving the substances in good solvents, such as water or alcohol. The liquid is then pumped into a nebulizer, where compressed air moving twice the speed of sound sprays the liquid droplets out through very narrow channels. It’s like a spray can on steroids. The droplets are completely dried between one to three microseconds from the time they are sprayed, leaving behind the amorphous nanoparticle.
At first, the amorphous structure of the nanoparticles was perplexing, said Esther Amstad, a former postdoctoral fellow in Weitz’ lab and current assistant professor at EPFL in Switzerland. Amstad is the paper’s first author. Then, the team realized that the nebulizer’s supersonic speed was making the droplets evaporate much faster than expected.
“If you’re wet, the water is going to evaporate faster when you stand in the wind,” said Amstad. “The stronger the wind, the faster the liquid will evaporate. A similar principle is at work here. This fast evaporation rate also leads to accelerated cooling. Just like the evaporation of sweat cools the body, here the very high rate of evaporation causes the temperature to decrease very rapidly, which in turn slows down the movement of the molecules, delaying the formation of crystals.”
These factors prevent crystallization in nanoparticles, even in materials that are highly prone to crystallization, such as table salt. The amorphous nanoparticles are exceptionally stable against crystallization, lasting at least seven months at room temperature.
The next step, Amstad said, is to characterize the properties of these new inorganic amorphous nanoparticles and explore potential applications.
“This system offers exceptionally good control over the composition, structure, and size of particles, enabling the formation of new materials,” said Amstad. “ It allows us to see and manipulate the very early stages of crystallization of materials with high spatial and temporal resolution, the lack of which had prevented the in-depth study of some of the most prevalent inorganic biomaterials. This systems opens the door to understanding and creating new materials.”
This research was coauthored by Manesh Gopinadhan, Christian Holtze, Chinedum O. Osuji, Michael P. Brenner, the Glover Professor of Applied Mathematics and Applied Physics and Professor of Physics, and Frans Spaepen, the John C. and Helen F. Franklin Professor of Applied Physics. It was supported by the National Science Foundation, Harvard MRSEC and BASF through the North American Center for Research on Advanced Materials (NORA), headed by Dr. Marc Schroeder.