Category Archives: Nanotechnology

Nanotechnology deals with the understanding and control of matter at dimensions between approximately 1 and 100 nanometers, where unique phenomena enable novel applications.

Dimensions between approximately 1 and 100 nanometers are known as the nanoscale.

Some examples to demonstrate the size of the nanoscale. ( Nanowerk) (click on image to enlarge)

The term was coined in 1974 by Norio Taniguichi of of Tokyo Science University to describe semiconductor processes such as thin-film deposition that deal with control on the order of nanometers. His definition still stands as the basic statement today: "Nano-technology mainly consists of the processing of separation, consolidation, and deformation of materials by one atom or one molecule."

Many argue that the history of nanotechnology starts with Richard Feynman's classic talk in December 1959: There's Plenty of Room at the Bottom - An Invitation to Enter a New Field of Physics:

Unusual physical, chemical, and biological properties can emerge in materials at the nanoscale. These properties may differ in important ways from the properties of bulk materials and single atoms or molecules.

The bulk properties of materials often change dramatically with nano ingredients. Composites made from particles of nano-size ceramics or metals smaller than 100 nanometers can suddenly become much stronger than predicted by existing materials-science models.

For example, metals with a so-called grain size of around 10 nanometers are as much as seven times harder and tougher than their ordinary counterparts with grain sizes in the hundreds of nanometers. The causes of these drastic changes stem from the weird world of quantum physics. The bulk properties of any material are merely the average of all the quantum forces affecting all the atoms. As you make things smaller and smaller, you eventually reach a point where the averaging no longer works.

The properties of materials can be different at the nanoscale for two main reasons:

Surface Area

Quantum Size Effects

Second, quantum effects can begin to dominate the behavior of matter at the nanoscale particularly at the lower end affecting the optical, electrical and magnetic behavior of materials. This effect describes the physics of electron properties in solids with great reductions in particle size. This effect does not come into play by going from macro to micro dimensions. However, it becomes dominant when the nanometer size range is reached.

The fascination with nanotechnology stems from these unique quantum and surface phenomena that matter exhibits at the nanoscale. They improve existing industrial processes, materials and applications in many fields and allows entirely new ones.

With regard to nanoscale materials, there are plenty of examples we could talk about here nanoparticles, quantum dots, nanowires, nanofibers, ultrathin-films, MXenes, etc.

One example, though, that is exemplary of how an 'old' material gets an exciting new life through nanoscale technologies is the element carbon.

Current applications of nanomaterials include very thin coatings used, for example, in electronics and active surfaces (such as self-cleaning windows). In most applications the nanomaterial will be fixed or embedded but in some, such as those used in cosmetics and in some environmental remediation applications, free nanoparticles are used. The ability to engineer materials to very high precision and accuracy (smaller than 100nm) is leading to considerable benefits in a wide range of industrial sectors, for instance in the production of components for the information and communication technology, automotive and aerospace industries.

A mite, less than 1 mm in size, approaching a microscale gear chain. (Image: Sandia National Laboratories)

Some 20-30 years ago, microelectromechanical systems (MEMS) emerged in industrial manufacturing in a major way. MEMS consist of any combination of mechanical (levers, springs, membranes, etc.) and electrical (resistors, capacitors, inductors, etc.) components to work as sensors or actuators. The size of today's smartphones would be impossible without the use of numerous MEMS devices. Apart from accelerometers and gyroscopes, smartphones contain micro-mirrors, image sensors, auto-focus actuators, pressure sensors, magnetometers, microphones, proximity sensors and many more. Another example from everyday life is the use of MEMS as accelerometers in modern automobile airbags where they sense rapid deceleration and, if the force is beyond a programmed threshold, initiate the inflation of the airbag.

Then, researchers took a further step down the size scale and have begun exploring another level of miniaturization nanoelectromechanical systems (NEMS). NEMS are showning great promise as highly sensitive detectors of mass, displacement, charge, and energy.

In some senses, nanoscience and nanotechnologies are not new. Chemists have been making polymers, which are large molecules made up of nanoscale subunits, for many decades and nanotechnologies have been used to create the tiny features on computer chips for the past 30 years.

However, advances in the tools that now allow individual atoms and molecules to be examined and probed with great precision have enabled the expansion and development of nanoscience and nanotechnologies. With new tools came new fundamental concepts and it turned out that the mechanical rules that govern the nanoworld are quite different from our everyday, macroworld experience.

Today there are a number of tools that can be used to characterize the nanomechanics of biomolecular and cellular interactions. Besides cantilever-based instruments like the AFM, examples include optical tweezers, and magnetic pullers.

Nano tech improves existing industrial processes, materials and applications by scaling them down to the nanoscale in order to ultimately fully exploit the unique quantum and surface phenomena that matter exhibits at the nanoscale. This trend is driven by companies' ongoing quest to improve existing products by creating smaller components and better performance materials, all at a lower cost.

A prime nanotechnology example of an industry where nanoscale manufacturing technologies are employed on a large scale and throughout is the semiconductor industry where device structures have reached the single nanometers scale. Your smartphone, smartwatch or tablet all are containing billions of transistors on a computer chip the size of a finger nail.

So, what can nanotechnology do? There is almost no field today where nanotechnology isn't applied in some form or shape as things like surface coatings, sensors, electronic components, membranes, etc. in medicine, environmental remediation, water filtration, nanoelectronics, food and agriculture, cosmetics, energy and batteries, space and aeronautics, automotive industries, displays, sports equipment and many more.

If you select "Introduction to Nanotechnology" from our menu bar above you will find numerous articles on all these topics in the right column.

Many products are defined as "nanotechnology product" because they contain nanoparticles in some form or other. For instance, many antimicrobial coatings contain silver in nanoscale form; food products and cosmetics contain nanoparticles; and some products are partially made with composite materials containing nanomaterials (e.g. carbon nanotubes or -fibers) to mechanically strengthen the material.

"Nanotech" products that are on the market today are mostly gradually improved products (using evolutionary nanotechnology) where some form of nano-enabled material (such as carbon nanotubes, graphene, nanocomposite structures or nanoparticles of a particular substance) or nanotech process (e.g. nanopatterning or quantum dots for medical imaging) is used in the manufacturing process.

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Nanotechnology - Definition and Introduction - Nanowerk

Potential applications of carbon nanotubesEdit

Nanotubes can help with cancer treatment. They have been shown to be effective tumor killers in those with kidney or breast cancer.[4][5] Multi-walled nanotubes are injected into a tumor and treated with a special type of laser that generates near-infrared radiation for around half a minute. These nanotubes vibrate in response to the laser, and heat is generated. When the tumor has been heated enough, the tumor cells begin to die. Processes like this one have been able to shrink kidney tumors by up to four-fifths.[4]

Ultrablack materials, made up of forests of carbon nanotubes, are important in space, where there is more light than is convenient to work with. Ultrablack material can be applied to camera and telescope systems to decrease the amount of light and allow for more detailed images to be captured.[6]

Nanotubes show promise in treating cardiovascular disease. They could play an important role in blood vessel cleanup. Theoretically, nanotubes with SHP1i molecules attached to them would signal macrophages to clean up plaque in blood vessels without destroying any healthy tissue. Researchers have tested this type of modified nanotube in mice with high amounts of plaque buildup; the mice that received the nanotube treatment showed statistically significant reductions in plaque buildup compared to the mice in the placebo group.[7] Further research is needed for this treatment to be given to humans.

Nanotubes may be used in body armor for future soldiers. This type of armor would be very strong and highly effective at shielding soldiers bodies from projectiles and electromagnetic radiation. It is also possible that the nanotubes in the armor could play a role in keeping an eye on soldiers conditions.[8]

Nanotechnology's ability to observe and control the material world at a nanoscopic level can offer great potential for construction development. Nanotechnology can help improve the strength and durability of construction materials, including cement, steel, wood, and glass.[9]

By applying nanotechnology, materials can gain a range of new properties. The discovery of a highly ordered crystal nanostructure of amorphous C-S-H gel and the application of photocatalyst and coating technology result in a new generation of materials with properties like water resistance, self-cleaning property, wear resistance, and corrosion protection.[10] Among the new nanoengineered polymers, there are highly efficient superplasticizers for concrete and high-strength fibers with exceptional energy absorbing capacity.[10]

Experts believe that nanotechnology remains in its exploration stage and has potential in improving conventional materials such as steel.[10] Understanding the composite nanostructures of such materials and exploring nanomaterials' different applications may lead to the development of new materials with expanded properties, such as electrical conductivity as well as temperature-, moisture- and stress-sensing abilities.[10]

Due to the complexity of the equipment, nanomaterials have high cost compared to conventional materials, meaning they are not likely to feature high-volume building materials.[11] In special cases, nanotechnology can help reduce costs for complicated problems. But in most cases, the traditional method for construction remains more cost-efficient.[11] With the improvement of manufacturing technologies, the costs of applying nanotechnology into construction have been decreasing over time and are expected to decrease more.[11]

Nanoelectronics refers to the application of nanotechnology on electronic components. Nanoelectronics aims to improve the performance of electronic devices on displays and power consumption while shrinking them.[3] Therefore, nanoelectronics can help reach the goal set up in Moore's law, which predicts the continued trend of scaling down in the size of integrated circuits.

Nanoelectronics is a multidisciplinary area composed of quantum physics, device analysis, system integration, and circuit analysis.[12] Since de Broglie wavelength in the semiconductors may be on the order of 100nm, the quantum effect at this length scale becomes essential.[12] The different device physics and novel quantum effects of electrons can lead to exciting applications.[12]

The terms nanobiotechnology and bionanotechnology refer to the combination of ideas, techniques, and sciences of biology and nanotechnology. More specifically, nanobiotechnology refers to the application of nanoscale objects for biotechnology while bionanotechnology refers to the use of biological components in nanotechnology.[1]

The most prominent intersection of nanotechnology and biology is in the field of nanomedicine, where the use of nanoparticles and nanodevices has many clinical applications in delivering therapeutic drugs, monitoring health conditions, and diagnosing diseases.[13] Being that much of the biological processes in the human body occur at the cellular level, the small size of nanomaterials allows for them to be used as tools that can easily circulate within the body and directly interact with intercellular and even intracellular environments. In addition, nanomaterials can have physiochemical properties that differ from their bulk form due to their size,[14] allowing for varying chemical reactivities and diffusion effects that can be studied and changed for diversified applications.

A common application of nanomedicine is in therapeutic drug delivery, where nanoparticles containing drugs for therapeutic treatment of disease are introduced into the body and act as vessels that deliver the drugs to the targeted area. The nanoparticle vessels, which can be made of organic or synthetic components, can further be functionalized by adjusting their size, shape, surface charge, and surface attachments (proteins, coatings, polymers, etc.).[15] The opportunity for functionalizing nanoparticles in such ways is especially beneficial when targeting areas of the body that have certain physiochemical properties that prevent the intended drug from reaching the targeted area alone; for example, some nanoparticles are able to bypass the Blood Brain Barrier to deliver therapeutic drugs to the brain.[16] Nanoparticles have recently been used in cancer therapy treatments and vaccines.[17][18]

In vivo imaging is also a key part in nanomedicine, as nanoparticles can be used as contrast agents for common imaging techniques such as computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET).[13] The ability for nanoparticles to localize and circulate in specific cells, tissues, or organs through their design can provide high contrast that results in higher sensitivity imaging, and thus can be applicable in studying pharmacokinetics or visual disease diagnosis.[13][15]

The energy applications of nanotechnology relates to using the small size of nanoparticles to store energy more efficiently. This promotes the use of renewable energy through green nanotechnology by generating, storing, and using energy without emitting harmful greenhouse gases such as carbon dioxide.

Nanoparticles used in solar cells are increasing the amount of energy absorbed from sunlight.[19] Solar cells are currently created from layers of silicon that absorb sunlight and convert it to usable electricity.[20] Using noble metals such as gold coated on top of silicon, researchers have found that they are able to transform energy more efficiently into electrical current.[20] Much of the energy that is loss during this transformation is due to heat, however by using nanoparticles there is less heat emitted thus producing more electricity.[20]

Nanotechnology is enabling the use of hydrogen energy at a much higher capacity.[21] Hydrogen fuel cells, while they are not an energy source themselves, allow for storing energy from sunlight and other renewable sources in an environmentally-friendly fashion without any CO2 emissions.[21] Some of the main drawbacks of traditional hydrogen fuel cells are that they are expensive and not durable enough for commercial uses.[22] However, by using nanoparticles, both the durability and price over time improve significantly.[22] Furthermore, conventional fuel cells are too large to be stored in volume, but researchers have discovered that nanoblades can store greater volumes of hydrogen that can then be saved inside carbon nanotubes for long-term storage.[22]

Nanotechnology is giving rise to nanographene batteries that can store energy more efficiently and weigh less.[23] Lithium-ion batteries have been the primary battery technology in electronics for the last decade, but the current limits in the technology make it difficult to densify batteries due to the potential dangers of heat and explosion.[21] Graphene batteries being tested in experimental electric cars have promised capacities 4 times greater than current batteries with the cost being 77% lower.[23] Additionally, graphene batteries provide stable life cycles of up to 250,000 cycles,[24] which would allow electric vehicles and long-term products a reliable energy source for decades.

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Applications of nanotechnology - Wikipedia

Nanotechnology is the understanding and control of matter at the nanoscale, at dimensions between approximately 1 and 100 nanometers, where unique phenomena enable novel applications. Matter can exhibit unusual physical, chemical, and biological properties at the nanoscale, differing in important ways from the properties of bulk materials, single atoms, and molecules. Some nanostructured materials are stronger or have different magnetic properties compared to other forms or sizes of the same material. Others are better at conducting heat or electricity. They may become more chemically reactive, reflect light better, or change color as their size or structure is altered.

Although modern nanoscience and nanotechnology are relatively new, nanoscale materials have been used for centuries. Gold and silver nanoparticles created colors in the stained-glass windows of medieval churches hundreds of years ago. The artists back then just didnt know that they were using nanotechnology to create these beautiful works of art!

Nanotechnology encompasses nanoscale science, engineering, and technology in fields such as chemistry, biology, physics, materials science, and engineering. Nanotechnology research and development involves imaging, measuring, modeling, and manipulating matter between approximately 1100 nanometers.

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About Nanotechnology | National Nanotechnology Initiative

Discover how progress in nanotechnology aid scientists to understand and apply the concept of particle engineering, specifically in the field of pharmacology

Nanotechnology is highly interdisciplinary, involving physics, chemistry, biology, materials science, and the full range of the engineering disciplines. The word nanotechnology is widely used as shorthand to refer to both the science and the technology of this emerging field. Narrowly defined, nanoscience concerns a basic understanding of physical, chemical, and biological properties on atomic and near-atomic scales. Nanotechnology, narrowly defined, employs controlled manipulation of these properties to create materials and functional systems with unique capabilities.

In contrast to recent engineering efforts, nature developed nanotechnologies over billions of years, employing enzymes and catalysts to organize with exquisite precision different kinds of atoms and molecules into complex microscopic structures that make life possible. These natural products are built with great efficiency and have impressive capabilities, such as the power to harvest solar energy, to convert minerals and water into living cells, to store and process massive amounts of data using large arrays of nerve cells, and to replicate perfectly billions of bits of information stored in molecules of deoxyribonucleic acid (DNA).

There are two principal reasons for qualitative differences in material behaviour at the nanoscale (traditionally defined as less than 100 nanometres). First, quantum mechanical effects come into play at very small dimensions and lead to new physics and chemistry. Second, a defining feature at the nanoscale is the very large surface-to-volume ratio of these structures. This means that no atom is very far from a surface or interface, and the behaviour of atoms at these higher-energy sites have a significant influence on the properties of the material. For example, the reactivity of a metal catalyst particle generally increases appreciably as its size is reducedmacroscopic gold is chemically inert, whereas at nanoscales gold becomes extremely reactive and catalytic and even melts at a lower temperature. Thus, at nanoscale dimensions material properties depend on and change with size, as well as composition and structure.

Using the processes of nanotechnology, basic industrial production may veer dramatically from the course followed by steel plants and chemical factories of the past. Raw materials will come from the atoms of abundant elementscarbon, hydrogen, and siliconand these will be manipulated into precise configurations to create nanostructured materials that exhibit exactly the right properties for each particular application. For example, carbon atoms can be bonded together in a number of different geometries to create variously a fibre, a tube, a molecular coating, or a wire, all with the superior strength-to-weight ratio of another carbon materialdiamond. Additionally, such material processing need not require smokestacks, power-hungry industrial machinery, or intensive human labour. Instead, it may be accomplished either by growing new structures through some combination of chemical catalysts and synthetic enzymes or by building them through new techniques based on patterning and self-assembly of nanoscale materials into useful predetermined designs. Nanotechnology ultimately may allow people to fabricate almost any type of material or product allowable under the laws of physics and chemistry. While such possibilities seem remote, even approaching natures virtuosity in energy-efficient fabrication would be revolutionary.

Even more revolutionary would be the fabrication of nanoscale machines and devices for incorporation into micro- and macroscale systems. Once again, nature has led the way with the fabrication of both linear and rotary molecular motors. These biological machines carry out such tasks as muscle contraction (in organisms ranging from clams to humans) and shuttling little packets of material around within cells while being powered by the recyclable, energy-efficient fuel adenosine triphosphate. Scientists are only beginning to develop the tools to fabricate functioning systems at such small scales, with most advances based on electronic or magnetic information processing and storage systems. The energy-efficient, reconfigurable, and self-repairing aspects of biological systems are just becoming understood.

The potential impact of nanotechnology processes, machines, and products is expected to be far-reaching, affecting nearly every conceivable information technology, energy source, agricultural product, medical device, pharmaceutical, and material used in manufacturing. Meanwhile, the dimensions of electronic circuits on semiconductors continue to shrink, with minimum feature sizes now reaching the nanorealm, under 100 nanometres. Likewise, magnetic memory materials, which form the basis of hard disk drives, have achieved dramatically greater memory density as a result of nanoscale structuring to exploit new magnetic effects at nanodimensions. These latter two areas represent another major trend, the evolution of critical elements of microtechnology into the realm of nanotechnology to enhance performance. They are immense markets driven by the rapid advance of information technology.

Learn about QED a play about physicist Richard Feynman, to teach science and engineering to people through performance art

In a lecture in 1959 to the American Physical Society, Theres Plenty of Room at the Bottom, American Nobelist Richard P. Feynman presented his audience with a vision of what could be done with extreme miniaturization. He began his lecture by noting that the Lords Prayer had been written on the head of a pin and asked,

Why cannot we write the entire 24 volumes of the Encyclopdia Britannica on the head of a pin? Lets see what would be involved. The head of a pin is a sixteenth of an inch across. If you magnify it by 25,000 diameters, the area of the head of the pin is then equal to the area of all the pages of the Encyclopdia Britannica. Therefore, all it is necessary to do is to reduce in size all the writing in the Encyclopdia by 25,000 times. Is that possible? The resolving power of the eye is about 1/120 of an inchthat is roughly the diameter of one of the little dots on the fine half-tone reproductions in the Encyclopdia. This, when you demagnify it by 25,000 times, is still 80 angstroms in diameter32 atoms across, in an ordinary metal. In other words, one of those dots still would contain in its area 1,000 atoms. So, each dot can easily be adjusted in size as required by the photoengraving, and there is no question that there is enough room on the head of a pin to put all of the Encyclopdia Britannica.

Feynman was intrigued by biology and pointed out that

cells are very tiny, but they are very active; they manufacture various substances; they walk around; they wiggle; and they do all kinds of marvelous thingsall on a very small scale. Also, they store information. Consider the possibility that we too can make a thing very small which does what we wantthat we can manufacture an object that maneuvers at that level!

He also considered using big tools to make smaller tools that could make yet smaller tools, eventually obtaining nanoscale tools for directly manipulating atoms and molecules. In considering what all this might mean, Feynman declared,

I can hardly doubt that when we have some control of the arrangement of things on a small scale we will get an enormously greater range of possible properties that substances can have, and of different things that we can do.

Perhaps the biggest barrier to following these prophetic thoughts was simply the immediate lack of tools to manipulate and visualize matter at such a small scale. The availability of tools has always been an enabling aspect of the advance of all science and technology, and some of the key tools for nanotechnology are discussed in the next section, Pioneers.

Starting with a 1981 paper in the Proceedings of the National Academy of Sciences and following with two popular books, Engines of Creation (1986) and Nanosystems (1992), American scientist K. Eric Drexler became one of the foremost advocates of nanotechnology. In fact, Drexler was the first person anywhere to receive a Ph.D. in molecular nanotechnology (from the Massachusetts Institute of Technology). In his written works he takes a molecular view of the world and envisions molecular machines doing much of the work of the future. For example, he refers to assemblers, which will manipulate individual atoms to manufacture structures, and replicators, which will be able to make multiple copies of themselves in order to save time dealing with the billions of atoms needed to make objects of useful size. In an article for Encyclopdia Britannicas 1990 Yearbook of Science and the Future, Drexler wrote:

Cells and tissues in the human body are built and maintained by molecular machinery, but sometimes that machinery proves inadequate: viruses multiply, cancer cells spread, or systems age and deteriorate. As one might expect, new molecular machines and computers of subcellular size could support the bodys own mechanisms. Devices containing nanocomputers interfaced to molecular sensors and effectors could serve as an augmented immune system, searching out and destroying viruses and cancer cells. Similar devices programmed as repair machines could enter living cells to edit out viral DNA sequences and repair molecular damage. Such machines would bring surgical control to the molecular level, opening broad new horizons in medicine.

Drexlers futurist visions have stimulated much thought, but the assembler approach has failed to account for the strong influence of atomic and molecular forces (i.e., the chemistry) at such dimensions. The controversy surrounding these popularizations, and the potential dangers of entities such as intelligent replicators (however remote), have stimulated debate over the ethical and societal implications of nanotechnology.

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Nanotechnology - Overview of nanotechnology | Britannica

NCI established the Nanotechnology Characterization Laboratory (NCL) to accelerate the progress of nanomedicine by providing preclinical characterization and safety testing of nanoparticles. It is a collaborative effort between NCI, the US Food and Drug Administration (FDA), and the National Institute of Standards and Technology (NIST).

The NCL serves as a resource and knowledge base for all cancer researchers in academia, industry, and government to facilitate the development and clinical translation of nanotechnologies intended as cancer therapeutics and diagnostics. NCL supports the characterization of:

Considering the relevance of nanoparticles to combat COVID-19 pandemic, the NCL also supports the characterization of nanotechnology-based COVID vaccines and therapeutics.

There are multiple ways the NCL can help nanotech researchers and developers advance their technology, including characterization, formulation, optimization, lead selection, and method development.

NCL has a free preclinical characterization service for developers of oncology-based nanoformulations to help in their development toward clinical trials.

Technical services are predefined statements of work for select NCL assays, with a fixed cost for each service. NCL provides two technical services, both based on the Stable Isotope Tracer Ultrafiltration Assay (SITUA) an analytical method invented at NCL that measures key nanomedicine fractions in plasma.

The NCL has developed a standardized analytical cascade that performs physicochemical characterization as well as preclinical testing of the immunology, pharmacology, and toxicology properties of nanomaterials. The data generated can be used in regulatory filings, in publications, and to garner interest from investors.

The NCL was founded in 2004 in collaboration with FDA and NIST, as a publicprivate partnership to advance the science needed to expedite the development of promising nanotech therapies and diagnostics. The NCL has tested more than 450 unique nanomaterials and worked with more than 125 investigators worldwide.

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Nanotechnology Characterization Laboratory - NCI

Nanotechnologies are new areas of research focusing on affecting matter at the atomic and molecular levels. It is beyond doubt that modern medicine can benefit greatly from it; thus nanomedicine has become one of the main branches of nanotechnological research. Currently it focuses on developing new methods of preventing, diagnosing and treating various diseases. Nanomaterials show very high efficiency in destroying cancer cells and are already undergoing clinical trials. The results are so promising that nanomaterials might become an alternative to traditional cancer therapy, mostly due to the fact that they allow cancer cells to be targeted specifically and enable detailed imaging of tissues, making planning further therapy much easier. Nanoscience might also be a source of the needed breakthrough in the fight against atherosclerosis, since nanostructures may be used in both preventing and increasing the stability of atherosclerotic lesions. One area of interest is creating nanomaterials that are not only efficient, but also well tolerated by the human body. Other potential applications of nanotechnology in medicine include: nanoadjuvants with immunomodulatory properties used to deliver vaccine antigens; the nano-knife, an almost non-invasive method of destroying cancer cells with high voltage electricity; and carbon nanotubes, which are already a popular way of repairing damaged tissues and might be used to regenerate nerves in the future. The aim of this article is to outline the potential uses of nanotechnology in medicine. Original articles and reviews have been used to present the new developments and directions of studies.

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Medical applications of nanotechnology - PubMed