Synopsis: Domenii: Nanotechnology:


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#Nanotechnology against malaria parasites Malaria parasites invade human red blood cells they then disrupt them and infect others. Researchers at the University of Basel and The swiss Tropical and Public health Institute have developed now so-called nanomimics of host cell membranes that trick the parasites.


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#New technique allows low-cost creation of 3-D nanostructures Researchers from North carolina State university have developed a new lithography technique that uses nanoscale spheres to create three-dimensional (3-D) structures

Our approach reduces the cost of nanolithography to the point where it could be done in your garage says Dr. Chih-Hao Chang an assistant professor of mechanical and aerospace engineering at NC State and senior author of a paper on the work.

The NC State researchers took a different approach placing nanoscale polystyrene spheres on the surface of the photosensitive film.

The nanospheres are transparent but bend and scatter the light that passes through them in predictable ways according to the angle that the light takes when it hits the nanosphere.

The researchers control the nanolithography by altering the size of the nanosphere the duration of light exposures and the angle wavelength and polarization of light.

The researchers can also use one beam of light or multiple beams of light allowing them to create a wide variety of nanostructure designs.

We are using the nanosphere to shape the pattern of light which gives us the ability to shape the resulting nanostructure in three dimensions without using the expensive equipment required by conventional techniques Chang says.

And it allows us to create 3-D structures all at once without having to make layer after layer of 2-D patterns.

The researchers have shown also that they can get the nanospheres to self-assemble in a regularly-spaced array

which in turn can be used to create a uniform pattern of 3-D nanostructures. This could be used to create an array of nanoneedles for use in drug delivery

or other applications says Xu Zhang a Ph d. student in Chang's lab and lead author of the paper.

The new technique could also be used to create nanoscale inkjet printers for printing electronics or biological cells or to create antennas or photonic components.

For this work we focused on creating nanostructures using photosensitive polymers which are used commonly in lithography Zhang says.

But the technique could also be used to create templates for 3-D structures using other materials.

We're exploring the use of nanosphere materials other than polystyrene as well as nanoparticle shapes other than spheres Chang says.

The paper Sculpting Asymmetric Hollow-Core Three-dimensional Nanostructures Using Colloidal Particles was published online Dec 8 in the journal Small l


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#Atomic'mismatch'creates nano'dumbbells'Like snowflakes nanoparticles come in a wide variety of shapes and sizes.

The geometry of a nanoparticle is often as influential as its chemical makeup in determining how it behaves from its catalytic properties to its potential as a semiconductor component.

Thanks to a new study from the U s. Department of energy's (DOE) Argonne National Laboratory researchers are closer to understanding the process by which nanoparticles made of more than one material called heterostructured nanoparticles form.

Heterostructured nanoparticles can be used as catalysts and in advanced energy conversion and storage systems. Typically these nanoparticles are created from tiny seeds of one material on top of

which another material is grown. In this study the Argonne researchers noticed that the differences in the atomic arrangements of the two materials have a big impact on the shape of the resulting nanoparticle.

Before we started this experiment it wasn't entirely clear what's happening at the interface

when one material grows on another said nanoscientist Elena Shevchenko of Argonne Center for Nanoscale Materials a DOE Office of Science user facility.

In this study the researchers observed the formation of a nanoparticle consisting of platinum and gold.

Initially the gold covered the platinum seed's surface uniformly creating a type of nanoparticle known as core-shell.

While the lattice mismatch is only fractions of a nanometer the effect accumulates as layer after layer of gold forms on the platinum.

As the gold continues to accumulate on one side of the seed nanoparticle small quantities slide down the side of the nanoparticle like grains of sand rolling down the side of a sand hill creating the dumbbell shape.

This is the first time anyone has been able to study the kinetics of this heterogeneous nucleation process of nanoparticles in real-time under realistic conditions said Argonne physicist Byeongdu Lee.

and the nanoscale which gave us a good view of how the nanoparticles form and transform.

This analysis of nanoparticle formation will help to lay the groundwork for the formation of new materials with different and controllable properties according to Shevchenko.

An article based on the research Heterogeneous nucleation and shape transformation of multicomponent metallic nanostructures appeared in the Nov 2 online issue of Nature Materials s


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#Scientists use'smallest possible diamonds'to form ultra-thin nanothreads For the first time scientists have discovered how to produce ultra-thin diamond nanothreads that promise extraordinary properties including strength and stiffness greater than that of today's strongest nanotubes

The team's discovery comes after nearly a century of failed attempts by other labs to compress separate carbon-containing molecules like liquid benzene into an ordered diamond-like nanomaterial.

The nanothread also may be the first member of a new class of diamond-like nanomaterials based on a strong tetrahedral core.

One of our wildest dreams for the nanomaterials we are developing is that they could be used to make the super-strong lightweight cables that would make possible the construction of a space elevator


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They have demonstrated for the first time the on-demand emission of electron pairs from a semiconductor quantum dot and verified their subsequent splitting into two separate conductors.

Their results have been published in the current online issue of the renowned journal Nature Nanotechnology. A precise control and manipulation of quantum-mechanical states could pave the way for promising applications such as quantum computers and quantum cryptography.


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#Nanoparticle network could bring fast-charging batteries (Phys. org) A new electrode design for lithium-ion batteries has been shown to potentially reduce the charging time from hours to minutes by replacing the conventional graphite electrode with a network of tin-oxide nanoparticles.

The anode consists of an ordered network of interconnected tin oxide nanoparticles that would be practical for commercial manufacture

When tin oxide nanoparticles are heated at 400 degrees Celsius they self-assemble into a network containing pores that allow the material to expand

Without the proper pore size and interconnection between individual tin oxide nanoparticles the battery fails. The research paper was authored by Etacheri;


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They describe their nanowire mesh design in the journal ACS Nano. Peidong Yang Bin Liu and colleagues note that harnessing sunlight to split water

The researchers took a page from the paper industry using one of its processes to make a flat mesh out of light-absorbing semiconductor nanowires that


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Scientists create multifunctional nanotubes using nontoxic materials A doctoral student in materials science at Technische Universitat Darmstadt is making multifunctional nanotubes of goldith the help of Vitamin c and other harmless substances.

The doctoral student in the research group of Professor Wolfgang Ensinger in the Department of Material Analysis is working on making nanotubes of gold.

The metal on the walls of the channels adopts the shape of nanotubes; the film is dissolved then.

The film with the nanochannels is placed merely in the precipitation bath.""It's really unbelievable that aqueous solutions

and simple basic chemicals can produce such precise nanostructures"says Münch.""Green meets Nano"is a motto of the researchers at the TU.

Its diameter can be set precisely-down to far less than 100 nanometers. The gold nanotubes are thus several hundred times finer than a human hair.

Their wall thickness depends both on the duration of precipitation and on the gold concentration of the original solution.

the result is-depending on the experimental conditions-a collection of individual nanotubes or an array of hundreds of thousands of interconnected tubes.

"With 1 gram of gold, we could make a nanotube for literally every person on earth."

Ensinger's team has tested already successfully one use of the gold nanotubes: they are suitable for building sensors to measure hydrogen peroxide.

The gold nanotubes conduct electricity especially well due to their one-dimensional structure. In addition, they are relatively long

and are thus more durable than normal nanoparticles.""Nano meets Life"is the second motto of the TU Materials science researchers.

For example, they are thinking about also using the nanotubes to measure blood sugar.""A subcutaneous sensor could save diabetes patients from having to constantly prick their fingers"thinks Ensinger.


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#Uniform nanowire arrays for science and manufacturing Defect-free nanowires with diameters in the range of 100 nanometers (nm) hold significant promise for numerous in demand applications including printable

Reproducible synthesis of gallium nitride nanowires with controlled size and location on silicon substrates. The result was achieved by improving selective wire-growth processes to produce one nanowire of controlled diameter per mask-grid opening over a range of diameters from 100 nm to 200 nm.

Ordered arrays with a variety of spacings were fabricated. In the near term the research will be used to create a wafer-scale arrays of probes for devices that examine the surface

and near-surface properties of materials to optimize nanowire LEDS and to produce nanowires with controlled diameter for a collaborative project involving printable transistors for millimeter-wave reconfigurable antennae e


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#Designing complex structures beyond the capabilities of conventional lithography Gold nanoparticles smaller than 10 nanometers spontaneously self-organize in entirely new ways

when trapped inside channel-like templates. A new study shows that this feature could facilitate easier nanoscale manufacturing of biosensors and plasmonic devices with intricate high-density surface structures.

Generating surface patterns at scales of 10 nanometers and below is difficult with current technology.

An international team led by Joel Yang from the A*STAR Institute of Materials Research and Engineering in Singapore is helping to circumvent this limitation using a technique known as'directed self-assembly of nanoparticles'(DSA-n). This approach takes spherical nanoparticles that spontaneously organize into ordered two-dimensional films

when inserted into lithographically defined templates. The templates impose geometric constraints that force the films to organize into specific nanoscale patterns.

Most patterns produced by DSA-n however are simple periodic arrangements. To broaden this technique's capabilities researchers are exploring'structure transitions'that occur

when template constraints become comparable to the size of the nanoparticles. At these dimensions the small spheres can dislocate from typical periodic positions

but direct imaging of sub-10-nanometer particles is nearly impossible. That's where we came up with the idea of using templates based on channels with gradually varying widths says co-author Mohamed Asbahi.

With this system we can track the self-assembly of the nanoparticles according to the space accessible to them.

Using electron-beam lithography techniques the team carved out an array of inward tapering trenches designed to fit 1 to 3 rows of gold nanoparticles.

After depositing a monolayer of 8-nanometer particles in the template they used scanning electron microscopy to identify any emergent width-dependent patterns.


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Researchers have been using electrodes made up of tiny silicon spheres about 150 nanometers wide#about a thousand times smaller than a human hair#to overcome some of the limitations of silicon as an electrode.

Last year materials scientist Chunmei Ban and her colleagues at the National Renewable energy Laboratory in Golden Colorado and the University of Colorado Boulder found that they could cover silicon nanoparticles with a rubberlike coating made from aluminum glycerol.

Researchers did not know how this coating improved the performance of the silicon nanoparticles. The nanoparticles naturally grow a hard shell of silicon oxide on their surface much like stainless steel forms a protective layer of chromium oxide on its surface.

No one understood if the oxide layer interfered with electrode performance and if so how the rubbery coating improved it.

So Yang He from the University of Pittsburgh explored the coated silicon nanoparticles in action at EMSL.

In the future the researchers would like to develop an easier method of coating the silicon nanoparticles. Explore further:

In situ Transmission Electron microscopy Probing of Native Oxide and Artificial Layers on Silicon Nanoparticles for Lithium ion batteries ACS Nano October 27 2014 DOI:


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This innovation in nanotechnology won't soak up enough carbon to solve global warming researchers say. However it will provide an environmentally friendly low-cost way to make nanoporous graphene for use in supercapacitors-devices that can store energy and release it rapidly.


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#Nanotubes may restore sight to blind retinas The aging process affects everything from cardiovascular function to memory to sexuality.

Yael Hanein of Tel aviv University's School of Electrical engineering and head of TAU's Center for Nanoscience and Nanotechnology and including researchers from TAU the Hebrew University of Jerusalem and Newcastle University.

The researchers combined semiconductor nanorods and carbon nanotubes to create a wireless light-sensitive flexible film that could potentially replace a damaged retina.

or older who have damage to a specific part of the retina will stand to benefit from the nanotube device

We hope our carbon nanotube and semiconductor nanorod film will serve as a compact replacement for damaged retinas.

We are still far away from actually replacing the damaged retina said Dr. Bareket. But we have demonstrated now that this new material stimulates neurons efficiently and wirelessly with light.


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#Nanomaterials to preserve ancient works of art Little would we know about history if it weren't for books and works of art.

In an effort to overcome the limitations of traditional restoration techniques the team has developed promising nanomaterials

This is where the NANOFORART (Nanomaterials for the conservation and preservation of movable and immovable artworks) project comes in.

The three-year project which ends this month has developed advanced nanomaterials for preventive conservation of works of art.

This involved nanomaterials that are physico-chemically compatible with the components of works of art

The advanced nanomaterials we have been working on allow for a more precise control of the restoration intervention for example controlled cleaning can be carried out using microemulsions and chemical hydrogels instead of traditional cleaning methods.

and solutions provided by advanced materials and colloid sciences and more generally nanosciences. These materials are able to resolve degradation issues

The first is the dispersion of calcium hydroxide nanoparticles in short chain alcohols for the consolidation of wall paintings plasters and stone.

The second is the dispersion of alkaline nanoparticles in either short chain alcohols or water for the ph control of movable works of art such as paper parchment and leather.

Dispersions of nanoparticles of calcium hydroxide for the consolidation of wall paintings plasters and stone are already available to conservators worldwide under the trademark Nanorestore.

Nanoparticles for the ph control of movable works of art (e g. paper wood canvas) have been branded under the trademark Nanorestore Paper;

This is the reason why we are proposing a new project within the Horizon 2020 call named NANORESTART (Nanomaterials for the RESTORARTION of the works of modern ART to highlight the new start with respect to classic art conservation) that aims


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and if the films were covered with catalytic nanoparticles such as platinum. The discovery makes monolayers of graphene

and its sister material boron nitride attractive for possible uses as proton-conducting membranes which are at the heart of modern fuel cell technology.

or monolayer boron nitride can allow the existing membranes to become thinner and more efficient with less fuel crossover and poisoning.


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Lawrence Livermore National Laboratory (LLNL) and The swiss Federal Institute of technology (ETH) researchers have developed a cost-effective and more efficient way to manufacture nanoporous metals over many scales from nanoscale to macroscale

The pattern is transformed in a single polymer mask with nanometer-size features. Last a technique known as anisotropic ion beam milling (IBM) is used to etch through the mask to make an array of holes creating the nanoporous metal.

which is key to creating the unique properties that make nanoporous materials work. The rougher the metal is the less evenly porous it becomes.

One of the biggest problems with this technique is that the metal layer cannot be peeled off uniformly (or at all) at the nanoscale.

because nanoporous materials facilitate anomalous enhancement of transmitted (or reflected light through the tunneling of surface plasmons a feature widely usable by light-emitting devices plasmonic lithography refractive-index-based sensing and all-optical switching.


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This ILLO process can enable not only nanoscale processes for high density flexible devices but also the high temperature process that was previously difficult to achieve on plastic substrates.

and substrate a nanoscale process at a high temperature of over 1000c can be utilized for high performance flexible electronics.


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The research, published today in Nature Nanotechnology, reports on nuclear pores in frog eggs and reveals how these pores can act like a supercharged sieve,

from the London Centre for Nanotechnology (UCL Mathematics & Physical sciences), said:""The pores have been known to act like a sieve that could hold back sugar


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First they made a sandwich composed of two metal electrodes separated by a two-nanometer thick insulating layer (a single nanometer is 10000 times smaller than a human hair) made by using a semiconductor technology called atomic layer deposition.

What is more the recognition tunneling technology we have developed allows us to make a relatively large gap (of two nanometers) compared to the much smaller gaps required previously for tunnel current read-out (which were less than a single nanometer wide.

Specifically when a current is passed through the nanopore as the DNA passes through it causes a spike in the current unique to each chemical base (A c T or G) within the DNA molecule.

while flowing through the two-nanometer gap. The research team is also working on modifying the technique to read other single molecules which could be used in an important technology for drug development.


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#Nanoparticles infiltrate kill cancer cells from within Conventional treatment seeks to eradicate cancer cells by drugs and therapy delivered from outside the cell

In contrast to conventional cancer therapy a University of Cincinnati team has developed several novel designs for iron-oxide based nanoparticles that detect diagnose

PTT uses the nanoparticles to focus light-induced heat energy only within the tumor harming no adjacent normal cells.

The UC study used the living cells of mice to successfully test the efficacy of their two-sided nanoparticle designs (one side for cell targeting and the other for treatment delivery) in combination with the PTT.

However the U s. Food and Drug Administration has approved now the use of iron-oxide nanoparticles in humans.

That means the photo-thermal effect of iron-oxide nanoparticles may show in the next decade a strong promise in human cancer therapy likely with localized tumors.

With this technology a low-power laser beam is directed at the tumor where a small amount of magnetic iron-oxide nanoparticles are present either by injecting the particles directly into the tumor

The nanomaterials enter only the abnormal cells illuminating those cells and then doing whatever it is you have designed them to do.

He stated With nanomaterial technology we can detect the tumor early and kill it on sight at the same time.

Scientists identify this certain biomarker that is specific to a certain tumor then conjugates this biomarker on the surface of the nanocarrier that only has the expression for that specific kind of cancer cell.

The nanotech carriers go into the body through a vein in the blood stream seek the abnormal cancer cells find the biomarker

The laser light heats the nanoparticles to at least 43 degrees Celsius to kill the cancer cells ultimately leaving all the other cells in the body unharmed.

Future research in nanoparticle PTT will look at toxicity biodegradability and compatibility issues. Shi said that the team is currently looking for other diverse biodegradable materials to use for the carriers such as plant chlorophylls like those in cabbage that are both edible and photothermal.


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We have created possibly the smallest-ever stereoscopic images using pixels formed from plasmonic nanostructures Yang told Phys. org.

metal nanostructures can scatter different wavelengths (colors) of light due to the fact that the tiny nanostructures themselves resonate at different wavelengths.

If a nanostructure is circular its resonance is polarization-independent because the diameter of the circle is the same from all directions.

However if a nanostructure is biaxial (such as an ellipse or rectangle) its resonance will depend on the polarization of the incident light.

To do this the researchers created nanopixels out of tiny pieces of aluminum a hundred or so nanometers across.

For example nanostructures that have circularly asymmetric shapes could have more than two polarization-dependent resonances due to the additional circularly polarized dimension.


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NTU associate professors Zhang Qichun and Joachim Loo have found a way to make the nanoparticle light up

The breakthrough has resulted in two papers published in Small one of the world's top scientific journals for material science and nanotechnology.

Prof Loo said their new biomarker can#also release anticancer drugs by creating a layer of coating loaded with drugs on the outside of the nanoparticle.#

and potentially target the delivery of drugs at the same time as proven in small animal tests said Prof Loo a nanotechnology and bioimaging expert.

Our breakthrough will open up new doors in the various fields of nanomedicine bioimaging and cancer therapeutics.

Inorganic#Organic Hybrid Nanoprobe for NIR-Excited Imaging of Hydrogen sulfide in Cell Cultures and Inflammation in a Mouse Model.


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#A gut reaction Queen's university biologist Virginia Walker and Queen's SARC Awarded Postdoctoral Fellow Pranab Das have shown nanosilver

The discovery is important as people are being exposed to nanoparticles every day. Nanosilver is used also in biomedical applications toys sunscreen cosmetics clothing and other items.

We were surprised to see significant upset of the human gut community at the lowest concentration of nanosilver in this study says Dr. Das.

To our knowledge this is the first time anyone has looked at this. It is important as we are exposed more and more to nanoparticles in our everyday lives through different routes such as inhalation direct contact or ingestion.

To conduct the research Drs. Walker and Das utilized another Queen's discovery repoopulate created by Elaine Petrof (Medicine.

In this instance rather than being used as therapy the synthetic stool was used to examine the impact of nanoparticles on the human gut.

The research showed that the addition of nanosilver reduced metabolic activity in the synthetic stool sample perturbed fatty acids

This information can help lead to an understanding of how nanoparticles could impact our gut ecosystem.

There is no doubt that the nanosilver shifted the bacterial community but the impact of nanosilver ingestion on our long-term health is currently unknown Dr. Walker says.

This is another area of research we need to explore. The findings by Drs. Das and Walker Julie AK Mcdonald (Kingston General Hospital) Dr. Petrof (KGH) and Emma Allen-Vercoe (University of Guelph) were published in the Journal of Nanomedicine and Nanotechnology.

Explore further: Building materials may impact Arctic tundra More information: omicsonline. org/open-access/na#157-7439.1000235. pd


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Silver nanowire ink which is highly conductive and stable offers a more practical solution. Hu's team wanted to develop a way to print it directly on paper to make a sensor that could respond to touch or specific molecules such as glucose.

Direct Writing on Paper of Foldable Capacitive Touch Pads with Silver nanowire Inks ACS Appl. Mater.

10.1021/am506987w Abstractpaper-based capacitive touch pads can be fabricated utilizing high-concentration silver nanowire inks needle-printed directly onto paper substrates through a 2d programmable platform.

Post deposition silver nanowire tracks can be sintered photonically using a camera flash to reduce sheet resistance similar to thermal sintering approaches.

Touch pad sensors on a variety of paper substrates can be achieved with optimized silver nanowire tracks.


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#Study suggests light may be skewing lab tests on nanoparticles'health effects Truth shines a light into dark places.

That's what recent findings at the National Institute of Standards and Technology (NIST) show about methods for testing the safety of nanoparticles.

It turns out that previous tests indicating that some nanoparticles can damage our DNA may have been skewed by inadvertent light exposure in the lab. Nanoparticles made of titanium dioxide are a common ingredient in paint

scientists have accepted long that these nanoparticles would not damage cells by forming free radicals from light activation.

whether light was required indeed for the nanoparticles to cause DNA damage.""We didn't set out to test the safety of the particles themselveshat's for someone else to determine,

"The NIST team exposed samples of DNA to titanium dioxide nanoparticles under three different conditions: Some samples were exposed in the presence of visible

"The results suggest that titanium dioxide nanoparticles do not damage DNA when kept in the dark,

must be controlled carefully before drawing conclusions about nanoparticle effects on DNA


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#Research team developing injectable treatment for soldiers wounded in battle Internal bleeding is a leading cause of death on the battlefield,

By inserting two-dimensional nanoplatelets into the hydrogel, the team was able to tweak the mechanical properties of material.

Two-dimensional materials are ultrathin substances with high surface area but a thickness of a few nanometers or less.

For example, a sheet of paper is 100,000 nanometers thick; Gaharwar's nanoplatelets are one nanometer thick. Gaharwar and his colleagues employ two-dimensional, disc-shaped particles known as synthetic silicate nanoplatelets.

Because of their shape, these platelets have a high surface area, he explains. The structure, composition and arrangement of the platelets result in both positive and negative charges on each particle.

These charges, Gaharwar explains, cause the platelets to interact with the hydrogel in a unique way.

these disc-shaped nanoplatelets interact with blood to promote clotting, Gaharwar says, noting that animal models have shown clot formation occurring in about one minute as opposed to five minutes without the presence of these nanoparticles.

Animal model, he adds, also have demonstrated the formation of lifesaving clot formations when the enhanced biomaterial was used."

"These 2d, silicate nanoparticles are unprecedented in the biomedical field, and their use promises to lead to both conceptual and therapeutic advances in the important and emerging field of tissue engineering, drug delivery, cancer therapies and immune engineering,


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