#'Trojan horse'proteins are step forward for nanoparticle-based anticancer and anti-dementia therapeutic approaches Scientists at Brunel University London have found a way of targeting hard-to-reach cancers
and degenerative diseases using nanoparticles but without causing the damaging side effects the treatment normally brings.
In a huge step forward in the use of nanomedicine the research helped discover proteins in the blood that disguise nanoparticles
so they are absorbed into cells without causing inflammation and destroying healthy cells. Two studies Complement activation by carbon nanotubes and its influence on the phagocytosis and cytokine response by macrophages and Complement deposition on nanoparticles can modulate immune responses by macrophage B
and T cells found that carbon nanotubes (CNTS) triggered a chain reaction in the complement system which is part of the innate immune system
and is responsible for clearing pathogens and toxins. The team led by Dr Uday Kishore of the Centre for Infection Immunity
and Disease Mechanisms found the entire complement system was activated from C1 at the start to C5 at the end.
This in turn activated the cell-killing membrane attack complex. In principle this should have caused an acute allergic inflammatory reaction.
However the opposite was true. The interaction between CNTS and C1q (a starter-protein for complement) was anti-inflammatory.
This suggests that either coating nanoparticles or healthy tissue with complement proteins could reduce tissue damage
and help treat inflammatory diseases like Parkinson's Huntington's ALS and Alzheimer's. It was not clear
if the binding between complement proteins and CNTS was direct or indirect. However changing the surfaces of CNTS affected how likely the complement system was to be activated and in what way.
Using the data from this study carbon nanoparticles coated with genetically-engineered proteins are being used to target glioblastoma the most aggressive form of brain tumour.
Dr Uday Kishore from Brunel University London's College of Health and Life sciences said: By using a protein recognised by the immune system to effectively disguise carbon nanoparticles we will be able to deploy these tiny particles to target hard-to-reach areas without damaging side effects to the patient.
This is a big step forward. It is like understanding how to use penicillin safely and could be as revolutionary to modern medicine as its twentieth century predecessor r
#Scalable growth of high quality bismuth nanowires Bismuth nanowires have intriguing electronic and energy harvesting application possibilities.
However fabricating these materials with high quality and in large quantities is challenging. A group at the CFN Brookhaven National Laboratory has demonstrated a new technique to produce single-crystal nanowires atop arbitrary substrates including glass silicon
and metal when an intermediate layer of vanadium is present.##The simplicity of the technique and the universality of the mechanism open a new avenue for the growth of nanowire arrays of a variety of materials.
This is the first report on the high yield(>70%)synthesis of single crystalline bismuth nanowires a material with potentially exploitable and intriguing thermoelectric properties.#
#This technique produces bismuth nanowires in quantities limited only by the size of the substrate on
which they are deposited.##The dimensions of the bismuth nanowires can be tuned over a very wide range simply by varying the substrate's temperature.#
#Further in contrast with other fabrication methods with this new technique there is no need for a catalyst to activate the production of the nanowires
thus avoiding inevitable contamination and enabling high-quality material. CFN Capabilities: CFN's Materials Synthesis and Characterization Electron microscopy and Advanced UV and X-ray Probes Facilities were used for synthesis of nanowires and their structural characterization.
Explore further: Uniform nanowire arrays for science and manufacturing More information: Surface energy induced formation of single crystalline bismuth nanowires over vanadium thin film at room temperature.
Nano Letters 14 5630#5635 (2014) DOI: 10.1021/nl502208 2
#New'electronic skin'for prosthetics robotics detects pressure from different directions Touch can be a subtle sense,
but it communicates quickly whether something in our hands is slipping, for example, so we can tighten our grip.
For the first time, scientists report the development of a stretchable"electronic skin"closely modeled after our own that can detect not just pressure,
but also what direction it's coming from. The study on the advance, which could have applications for prosthetics
and robotics, appears in the journal ACS Nano. Hyunhyub Ko and colleagues explain that electronic skins are flexible
film-like devices designed to detect pressure, read brain activity, monitor heart rate or perform other functions.
To boost sensitivity to touch, some of them mimic microstructures found in beetles and dragonflies, for example,
but none reported so far can sense the direction of stress. This is the kind of information that can tell our bodies a lot about the shape
and texture of an object and how to hold it. Ko's team decided to work on an electronic skin based on the structure of our own so it could"feel"in three dimensions.
The researchers designed a wearable artificial skin made out of tiny domes that interlock and deform when poked
or even when air is blown across it. It could sense the location, intensity and direction of pokes, air flows and vibrations.
Abstract Stretchable electronic skins with multidirectional force-sensing capabilities are of great importance in robotics, prosthetics,
piezoresistive interlocked microdome arrays are employed for stress-direction-sensitive, stretchable electronic skins. Here we show that these arrays possess highly sensitive detection capability of various mechanical stimuli including normal,
In addition, we show that the electronic skins attached on human skin in the arm and wrist areas are able to distinguish various mechanical stimuli applied in different directions
#Contact lens merges plastics and active electronics via 3-D printing (Phys. org) As part of a project demonstrating new 3-D printing techniques Princeton researchers have embedded tiny light-emitting diodes into a standard contact lens
allowing the device to project beams of colored light. Michael Mcalpine the lead researcher cautioned that the lens is designed not for actual use for one it requires an external power supply.
Instead he said the team created the device to demonstrate the ability to 3-D print electronics into complex shapes and materials.
This shows that we can use 3-D printing to create complex electronics including semiconductors said Mcalpine an assistant professor of mechanical and aerospace engineering.
We were able to 3-D print an entire device in this case an LED. The hard contact lens is made of plastic.
The researchers used tiny crystals called quantum dots to create the LEDS that generated the colored light.
We used the quantum dots also known as nanoparticles as an ink Mcalpine said. We were able to generate two different colors orange and green.
In the recent past a team of Princeton professors including Mcalpine created a bionic ear out of living cells with an embedded antenna that could receive radio signals.
The main focus of the bionic ear project was to demonstrate the merger of electronics
and biological materials said Kong a graduate student in mechanical and aerospace engineering. Kong the lead author of the Oct 31 article describing the current work in the journal Nano Letters said that the contact lens project on the other hand involved the printing of active electronics using diverse materials.
The materials were often mechanically chemically or thermally incompatible for example using heat to shape one material could inadvertently destroy another material in close proximity.
and also had to develop new methods to print electronics rather than use the techniques commonly used in the electronics industry.
For example it is not trivial to pattern a thin and uniform coating of nanoparticles and polymers without the involvement of conventional microfabrication techniques yet the thickness and uniformity of the printed films are two of the critical parameters that determine the performance
and yield of the printed active device Kong said. To solve these interdisciplinary challenges the researchers collaborated with Ian Tamargo who graduated this year with a bachelor's degree in chemistry;
Hyoungsoo Kim a postdoctoral research associate and fluid dynamics expert in the mechanical and aerospace engineering department;
and Barry Rand an assistant professor of electrical engineering and the Andlinger Center for Energy and the Environment.
Mcalpine said that one of 3-D printing's greatest strengths is its ability to create electronics in complex forms.
Unlike traditional electronics manufacturing which builds circuits in flat assemblies and then stacks them into three dimensions 3-D printers can create vertical structures as easily as horizontal ones.
In this case we had a cube of LEDS he said. Some of the wiring was vertical
and some was horizontal. To conduct the research the team built a new type of 3-D printer that Mcalpine described as somewhere between off-the-shelf and really fancy.
Dan Steingart an assistant professor of mechanical and aerospace engineering and the Andlinger Center helped design and build the new printer
which Mcalpine estimated cost in the neighborhood of $20000. Mcalpine said that he does not envision 3-D printing replacing traditional manufacturing in electronics any time soon;
instead they are complementary technologies with very different strengths. Traditional manufacturing which uses lithography to create electronic components is a fast and efficient way to make multiple copies with a very high reliability.
Manufacturers are using 3-D printing which is slow but easy to change and customize to create molds and patterns for rapid prototyping.
Prime uses for 3-D printing are situations that demand flexibility and that need to be tailored to a specific use.
For example conventional manufacturing techniques are not practical for medical devices that need to be fit to a patient's particular shape
or devices that require the blending of unusual materials in customized ways. Trying to print a cellphone is probably not the way to go Mcalpine said It is customization that gives the power to 3-D printing.
In this case the researchers were able to custom 3-D print electronics on a contact lens by first scanning the lens and feeding the geometric information back into the printer.
This allowed for conformal 3-D printing of an LED on the contact lens s
#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.
This could lead to novel treatment and vaccination strategies in the fight against malaria and other infectious diseases.
Their research results have been published in the scientific journal ACS Nano. For many infectious diseases no vaccine currently exists.
In addition resistance against currently used drugs is spreading rapidly. To fight these diseases innovative strategies using new mechanisms of action are needed.
The malaria parasite Plasmodium falciparum that is transmitted by the Anopheles mosquito is such an example. Malaria is still responsible for more than 600000 deaths annually especially affecting children in Africa (WHO 2012.
Malaria parasites normally invade human red blood cells in which they hide and reproduce. They then make the host cell burst
and infect new cells. Using nanomimics this cycle can now be disrupted effectively: The egressing parasites now bind to the nanomimics instead of the red blood cells.
Researchers of groups led by Prof. Wolfgang Meier Prof. Cornelia Palivan (both at the University of Basel) and Prof.
Hans-Peter Beck (Swiss TPH) have designed successfully and tested host cell nanomimics. For this they developed a simple procedure to produce polymer vesicles small artificial bubbles with host cell receptors on the surface.
The preparation of such polymer vesicles with water-soluble host receptors was done by using a mixture of two different block copolymers.
In aqueous solution the nanomimics spontaneously form by self-assembly. Usually the malaria parasites destroy their host cells after 48 hours
and then infect new red blood cells. At this stage they have to bind specific host cell receptors.
and the reduction of infection through the nanomimics was 100-fold higher when compared to a soluble form of the host cell receptors.
and vaccines strategies in the future says Adrian Najer first-author of the study. Since many other pathogens use the same host cell receptor for invasion the nanomimics might also be used against other infectious diseases.
The research project was funded by The swiss National Science Foundation and the NCCR Molecular Systems Engineering.
Why humans don't suffer from chimpanzee malaria More information: Adrian Najer Dalin Wu Andrej Bieri Franoise Brand Cornelia G. Palivan Hans-Peter Beck and Wolfgang Meier.
ACS Nano Publication Date (Web: November 29 2014 DOI: 10.1021/nn505420 0
#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
with biomedical electronic and photonic applications. The new technique is significantly less expensive than conventional methods
and does not rely on stacking two-dimensional (2-D) patterns to create 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.
Most conventional lithography uses a variety of techniques to focus light on a photosensitive film to create 2-D patterns.
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.
The researchers are currently looking at several additional ways to manipulate the technique to control the shape of resulting structures.
We're exploring the use of nanosphere materials other than polystyrene as well as nanoparticle shapes other than spheres Chang says.
And ultimately we want to look at ways of controlling the placement of particles on the photosensitive film in patterns other than uniform arrays.
The paper Sculpting Asymmetric Hollow-Core Three-dimensional Nanostructures Using Colloidal Particles was published online Dec 8 in the journal Small l
#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.
Thanks to state-of-the-art X-ray analysis provided by Argonne's Advanced Photon Source (APS) a DOE Office of Science user facility the researchers identified the cause of the dumbbell formation as lattice mismatch in
While the lattice mismatch is only fractions of a nanometer the effect accumulates as layer after layer of gold forms on the platinum.
The mismatch can be handled by the first two layers of gold atoms creating the core-shell effect
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.
All conclusions made based on the X-ray studies were confirmed further using atomic-resolution microscopy in the group of Professor Robert Klie of the University of Illinois at Chicago.
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.
The research was funded in part by the National Science Foundation and the University of Illinois at Chicago Research Resources Center.
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
#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
and polymers. A paper describing this discovery by a research team led by John V. Badding a professor of chemistry at Penn State was published in the Sept. 21 issue of the journal Nature Materials.
From a fundamental-science point of view our discovery is intriguing because the threads we formed have a structure that has never been seen before Badding said.
The core of the nanothreads that Badding's team made is a long thin strand of carbon atoms arranged just like the fundamental unit of a diamond's structure zigzag cyclohexane rings of six carbon atoms bound together in
It is as if an incredible jeweler has strung together the smallest possible diamonds into a long miniature necklace Badding said.
Because this thread is diamond at heart we expect that it will prove to be extraordinarily stiff extraordinarily strong and extraordinarily useful.
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.
and to link up in a highly ordered chain of single-file carbon tetrahedrons forming these diamond-core nanothreads.
He describes the thread's width as phenomenally small only a few atoms across hundreds of thousands of times smaller than an optical fiber enormously thinner that an average human hair.
The molecule they compressed is benzene a flat ring containing six carbon atoms and six hydrogen atoms.
The resulting diamond-core nanothread is surrounded by a halo of hydrogen atoms. During the compression process the scientists report the flat benzene molecules stack together bend
The result is a structure that has carbon in the tetrahedral configuration of diamond with hydrogens hanging out to the side and each tetrahedron bonded with another to form a long thin nanothread.
so that when we release the pressure very slowly an orderly polymerization reaction happens that forms the diamond-core nanothread.
The scientists confirmed the structure of their diamond nanothreads with a number of techniques at Penn State Oak ridge Arizona State university
Parts of these first diamond nanothreads appear to be somewhat less than perfect so improving their structure is a continuing goal of Badding's research program.
The high pressures that we used to make the first diamond nanothread material limit our production capacity to only a couple of cubic millimeters at a time so we are not yet making enough of it to be useful on an industrial scale Badding said.
One of our science goals is to remove that limitation by figuring out the chemistry necessary to make these diamond nanothreads under more practical conditions.
The nanothread also may be the first member of a new class of diamond-like nanomaterials based on a strong tetrahedral core.
Our discovery that we can use the natural alignment of the benzene molecules to guide the formation of this new diamond nanothread material is really interesting
You can attach all kinds of other atoms around a core of carbon and hydrogen.
and therefore less-polluting vehicles. 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
which so far has existed only as a science-fiction idea Badding said d
#Controlled emission and spatial splitting of electron pairs demonstrated In quantum optics generating entangled and spatially separated photon pairs (e g. for quantum cryptography) is already a reality.
So far it has however not been possible to demonstrate an analogous generation and spatial separation of entangled electron pairs in solids.
Physicists from Leibniz University Hannover and from the Physikalisch-Technische Bundesanstalt (PTB) have taken now a decisive step in this direction.
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.
In quantum optics such experiments have already been performed for some time. This for example allows the controlled generation of pairs of entangled but spatially separated photons
which are of essential importance for quantum cryptography. An analogous generation and spatial separation of entangled electrons in solids would be of fundamental importance for future applications
As an electron source the physicists from Leibniz University Hannover and from PTB used so-called semiconductor single-electron pumps.
This is an important step towards the envisioned generation and separation of entangled electron pairs in semiconductor components s
#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.
Batteries have called two electrodes an anode and a cathode. The anodes in most of today's lithium-ion batteries are made of graphite.
The theoretical maximum storage capacity of graphite is limited very at 372 milliamp hours per gram hindering significant advances in battery technology said Vilas Pol an associate professor of chemical engineering at Purdue University.
The researchers have performed experiments with a porous interconnected tin-oxide based anode which has nearly twice the theoretical charging capacity of graphite.
The researchers demonstrated that the experimental anode can be charged in 30 minutes and still have a capacity of 430 milliamp hours per gram (mah g 1)
which is greater than the theoretical maximum capacity for graphite when charged slowly over 10 hours.
The anode consists of an ordered network of interconnected tin oxide nanoparticles that would be practical for commercial manufacture
because they are synthesized by adding the tin alkoxide precursor into boiling water followed by heat treatment Pol said.
We are not using any sophisticated chemistry here Pol said. This is very straightforward rapid'cooking'of a metal-organic precursor in boiling water.
The precursor compound is a solid tin alkoxide a material analogous to cost-efficient and broadly available titanium alkoxides.
It will certainly become fully affordable in the perspective of broad scale application mentioned by collaborators Vadim G. Kessler and Gulaim A. Seisenbaeva from the Swedish University of Agricultural sciences.
Findings are detailed in a paper published in November in the journal Advanced Energy Materials.
When tin oxide nanoparticles are heated at 400 degrees Celsius they self-assemble into a network containing pores that allow the material to expand
and contract or breathe during the charge-discharge battery cycle. These spaces are very important for this architecture said Purdue postdoctoral research associate Vinodkumar Etacheri.
Without the proper pore size and interconnection between individual tin oxide nanoparticles the battery fails. The research paper was authored by Etacheri;
Swedish University of Agricultural sciences researchers Gulaim A. Seisenbaeva Geoffrey Daniel and Vadim G. Kessler; James Caruthers Purdue's Gerald and Sarah Skidmore Professor of Chemical engineering;
Jeanmarie Nedelec a researcher from Clermont Universit in France; and Pol l
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