#Major innovation in molecular imaging delivers spatial and spectral info simultaneously Using physical chemistry methods to look at biology at the nanoscale,
Ke Xu, a faculty scientist in Berkeley Lab Life sciences Division, has dubbed his innovation SR-STORM,
the technology opens the door to high-resolution imaging of multiple components and local chemical environments,
Xu is also an assistant professor at UC Berkeley Department of chemistry. e measure both the position and spectrum of each individual molecule, plotting its super-resolved spatial position in two dimensions and coloring each molecule according to its spectral position,
Xu built on work he did as a postdoctoral researcher at Harvard with Xiaowei Zhuang, who invented STORM, a super-resolution microscopy method based on single-molecule imaging and photoswitching.
and back of the sample at the same time and achieved unprecedented optical resolution (of approximately 10 nanometers) of a cell.
so we solved the conundrum. ext they dyed the sample with 14 different dyes in a narrow emission window and excited and photoswitched the molecules with one laser.
and thus readily identifiable. hat useful because it means we had a way to do multicolor imaging within a very narrow emission window,
and each subcellular structure was a distinct color. o using this method we can look at interactions between four biological components inside a cell in three-dimension and at very high resolution of about 10 nanometers,
Xu said. he applications are mostly in fundamental research and cell biology at this point, but hopefully it will lead to medical applications.
This gives us new opportunities to look at cell structures how theye built up, and whether there any degradation of those structures in diseases. any diseases are caused either by an invading pathogen or degradation of a cell internal structure.
Alzheimer, for example, may be related to degradation of the cytoskeleton inside neurons. he cytoskeleton system is comprised of a host of interacting subcellular structures and proteins,
and make it work with conventional microscope systems, thus making it more broadly accessible. He is also trying to develop suitable dyes
and probes to monitor the local environment, such as the ph, in live cells at the nanometer scale.
Image: A spectrally resolved super-resolution microscopy image of four subcellular targets that were labeled by four far-red dyes at 10 nm spectral separation.
The work revolves around a family of compounds called metal-organic frameworks (MOFS), which are cage-like structures consisting of metal ions,
linked by organic bonds. Their porous properties have led to proposed application in carbon capture, hydrogen storage and toxic gas separations,
due to their ability to selectively adsorb and store preselected target molecules, much like a building a sieve
and mechanical properties of MOFS compared to materials such as ceramics or metals, and have resulted in the past in structural collapse during postprocessing techniques such as sintering
Dr Thomas Bennett from the Department of Materials science and Metallurgy at the University of Cambridge says:
raditional methods used in melt-casting of metals or sintering of ceramics cause the structural collapse of MOFS due to the structures thermally degrading at low temperatures.
Through exploring the interface between melting, recrystallisation and thermal decomposition, we now should be able to manufacture a variety of shapes
Professor Yuanzheng Yue from Aalborg University adds: second facet to the work is in the glasses themselves,
which appear distinct from existing categories. The formation of glasses that contain highly interchangeable metal and organic components,
in is highly unusual, as they are normally either purely organic, for example in solar cell conducting polymers,
or entirely inorganic, such as oxide or metallic glasses. Understanding the mechanism of hybrid glass formation will also greatly contribute to our knowledge of glass formers in general.
Using the advanced capabilities at the UK synchrotron, Diamond Light source, the team were able to scrutinise the metal organic frameworks in atomic detail.
Professor Trevor Rayment Physical science Director at Diamond, comments:""This work is an exciting example of how work with synchrotron radiation
which deepens our fundamental understanding of the properties of glasses also produces tantalising prospects of practical applications of new materials.
This work could have a lasting impact on both frontiers of knowledge. The researchers believe the new technique could open up the possibility of the production of'chemically designed'glasses
whereby different metals or organics are swapped into, or out of, the MOFS before melting o
#Butterfly wings help break the status quo in gas sensing The unique properties found in the stunning iridescent wings of a tropical blue butterfly could hold the key to developing new highly selective gas detection sensors.
Pioneering new research by a team of international scientists, including researchers from the University of Exeter,
has replicated the surface chemistry found in the iridescent scales of the Morpho butterfly to create an innovative gas sensor.
The ground-breaking findings could help inspire new designs for sensors that could be used in a range of sectors,
including medical diagnostics, industry, and the military. The research, published in the highly respected scientific journal, Nature Communications on September 1st, describes how the composition of gases in different environments can be detected by measuring small colour changes of the innovative bio-inspired sensor.
Professor Pete Vukusic, one of the authors of the research and part of the Physics department at the University of Exeter said:
io-inspired approaches to the realisation of new technologies are tremendously valuable. In this work, by developing a detailed understanding of the subtle way in
which the appearance and colour of the Morpho butterfly arises, and the way this colour depends on its local environment,
our team has discovered a remarkable way in which we can advance sensor and detector technology rapidly.
Tiny treelike nanostructures in the scales of Morpho wings are known to be responsible for the butterfly brilliant iridescence.
Previous studies have shown that vapour molecules adhere differently to the top of these structures than to the bottom due to local chemistry within the scales.
This selective response to vapour molecules is the key to this bio-inspired gas sensor.
The research team, led by scientists from GE Global Research in the USA and also comprised of University of Exeter, State university of New york at Albany,
and Air force Research Laboratory, produced these new kind of colorimetric sensors that favourably compete with conventional gas sensor arrays in simplicity, stability,
and cost-savings. At present, reliable and cost-effective sensors for detection of small but meaningful gas leaks in a multitude of industrial processes remain an unmet environmental, health,
and safety goal. The research team believe this highly selective colorimetric sensor could represent a significant advancement in gas leak detection performance in the future.
Dr. Radislav Potyrailo the study lead author and Principal Scientist at Global Research headquarters in Niskayuna, New york, said:
aterial-design principles applied in nature impact many scientific fields. We found the origin of the unusually high gas selectivity of the wing scales of Morpho butterflies
and fabricated a new kind of gas sensor based on these principles. hese new sensors not only selectively detect separate gases
Our next goal is to make these sensors in a cost-effective manner to offer new attractive sensing solutions in the marketplace.
Dr. Timothy Starkey, researcher at the University of Exeter, said: ur research into these bio-inspired sensors demonstrates the huge value in applying the scientific learnings from the biological world to develop technologies for real world applications. d
#Making 3d objects disappear Invisibility cloaks are a staple of science fiction and fantasy, from Star trek to Harry potter,
Scientists at the U s. Department of energy (DOE) Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley have devised an ultra-thin invisibility kincloak that can conform to the shape
Working with brick-like blocks of gold nanoantennas, the Berkeley researchers fashioned a kin cloakbarely 80 nanometers in thickness,
that was wrapped around a three-dimensional object about the size of a few biological cells and arbitrarily shaped with multiple bumps and dents.
director of Berkeley Lab Materials sciences Division and a world authority on metamaterials artificial nanostructures engineered with electromagnetic properties not found in nature. ur ultra-thin cloak now looks like a coat.
and is a member of the Kavli Energy Nanosciences Institute at Berkeley (Kavli ENSI), is the corresponding author of a paper describing this research in Science.
It is the scattering of light be infrared it visible , X-ray, etc.,from its interaction with matter that enables us to detect
The rules that govern these interactions in natural materials can be circumvented in metamaterials whose optical properties arise from their physical structure rather than their chemical composition.
For the past ten years, Zhang and his research group have been pushing the boundaries of how light interacts with metamaterials,
In the past, their metamaterial-based optical carpet cloaks were bulky and hard to scale up and entailed a phase difference between the cloaked region
what it concealed was not. reating a carpet cloak that works in air was so difficult we had embed to it in a dielectric prism that introduced an additional phase in the reflected light,
a recent member of Zhang research group who is now an assistant professor at Penn State university. ecent developments in metasurfaces,
however, allow us to manipulate the phase of a propagating wave directly through the use of subwavelength-sized elements that locally tailor the electromagnetic response at the nanoscale,
300 square microns in area that was wrapped conformally in the gold nanoantenna skin cloak, the light reflected off the surface of the skin cloak was identical to light reflected off a flat mirror,
The cloak can be turned nor ffsimply by switching the polarization of the nanoantennas. phase shift provided by each individual nanoantenna fully restores both the wavefront
and metamaterials offers tantalizing future prospects for technologies such as high resolution optical microscopes and superfast optical computers.
At the macroscale, among other applications, invisibility cloaks could prove useful for 3d displays i
which uses nanopores to read individual nucleotides, paves the way for better and cheaper DNA sequencing.
One of the most critical biological and medical tools available today, it lies at the core of genome analysis. Reading the exact make-up of genes,
scientists can detect mutations, or even identify different organisms. A powerful DNA sequencing method uses tiny
The breakthrough is published in Nature Nanotechnology. Reading too fast DNA is a long molecule made up of four repeating different building-blocks.
These are called ucleotidesand are strung together in various combinations that contain the cell genetic information, such as genes.
In nanopore sequencing, DNA passes through a tiny pore in a membrane, much like a thread goes through a needle.
Slowing things down The lab of Aleksandra Radenovic at EPFL Institute of Bioengineering has now overcome the problem of speed by using a thick,
viscous liquid that slows the passage of DNA two to three orders of magnitude. As a result, sequencing accuracy improves down to single nucleotides.
The team then created a nanopore on membrane, almost 3 nm wide. The next step was to dissolve DNA in a thick liquid that contained charged ions and
the team tested their system by passing known nucleotides, dissolved in the liquid, through the nanopore multiple times.
Although still at a testing stage, the team is aiming to continue their work by testing entire DNA strands. e are seeking opportunities to commercialize this technique,
which is promising for sequencing with solid-state nanopores, says Jiandong Feng. The scientists also predict that using high-end electronics
and control of the viscosity gradient of the liquid could further optimize the system. By combining ionic liquids with nanopores on molybdenum disulfide thin films
they hope to create a cheaper DNA sequencing platform with a better output. The work offers an innovative way that can improve one of the best DNA sequencing methods available. n years to come,
sequencing technology will definitely shift from research to clinics, says Aleksandra Radenovic. or that, we need rapid and affordable DNA sequencing
and nanopore technology can deliver. n
#New graphene oxide biosensors may accelerate research of HIV and cancer drugs Longing to find a cure for cancer, HIV and other yet incurable diseases,
researchers have tried already out hundreds of drugs, each requiring preclinical and clinical testing with live subjects.
How many chemical agents more to try? Moving at such rate, will we find the cure during our lifetime?
One of the easiest ways to speed up the drug development process is to simply perform it outside of the living body (e g.,
This approach will eventually provide more effective preclinical selection of drug candidates for the subsequent long-term and expensive clinical trial.
and vaccines against many dangerous diseases including HIV, hepatitis and cancer. The research, led by Yury Stebunov,
a scientist at the MIPT, was published in the ACS Applied materials & Interfaces. The paper is titled"Highly sensitive and selective sensor chips with graphene oxide linking layer".
"Valentyn Volkov is the co-lead author, a visiting professor from the University of Southern Denmark.
Other co-authors are Olga Aftenieva and Aleksey Arsenin. New GO based biosensor chips exploit the phenomenon of surface plasmon resonance (SPR.
Surface plasmons are electromagnetic waves propagating along a metal-dielectric interface (e g.,, gold/air) and having the amplitudes exponentially decaying in the neighbor media.
Adsorption of molecules from solution onto a sensing surface alters the refractive index of the medium near this surface and,
therefore, changes the conditions of SPR. These sensors can detect biomolecule adsorption even at a few trillionth of a gram per millimeter square.
Owing to the above-mentioned merits, SPR biosensing is an outstanding platform to boost technological progress in the areas of medicine and biotechnology.
Nevertheless, the most distinctive feature of such sensors is an ability to isualizemolecular interactions in real time.
PR biosensing is a valuable tool to investigate a wide range of biochemical reactions estimate their chemical kinetics and other characteristics.
All this can be used efficiently for new drug discovery and validation. Widespread introduction of this method into preclinical trials will completely change the pharmaceutical industry.
With SPR sensors we just need to estimate the interaction between the drug and targets on the sensing surface,
Stebunov said. Most commercial SPR sensor chips comprise a thin glass plate covered by gold layer with thiol
or polymer layers on it. The biosensing sensitivity depends on the properties of chip surface. Higher binding capacity for biomolecules increases the signal levels and accuracy of analysis. The last several years
novel carbon materials like graphene have attracted much attention due to their large surface area, low-cost fabrication, and interaction with a wide range of biomolecules.
Stebunov and the team from the Laboratory of Nanooptics and Plasmonics at MIPT created and patented a novel type of SPR sensor chips with the linking layer,
made of GO, a material with more attractive optical and chemical properties than pristine graphene. The GO lakeswere deposited on the 35 nm gold layer.
Thereafter a layer of streptavidin protein was developed on GO FOR selective immobilization of biomolecules. Scientists conducted a series of experiments with the GO chip
the commercially available chip with carboxymethylated dextran (CMD) layer and the chip covered by monolayer graphene.
Experiments showed that the proposed GO chip has three times higher sensitivity than the CMD chip and 3. 7 times than the chip with pristine graphene.
These results mean, that the new chip needs much less molecules for detecting a compound
and can be used for analysis of chemical reactions with small drug molecules. An important advantage of the new GO based sensor chips is their simplicity
and low-cost fabrication compared to sensor chips that are already commercially available. ur invention will help in drug development against viral and cancer diseases.
We are expecting that pharmaceutical industry will express a strong demand for our technology Stebunov said. he sensor can also find applications in food quality control, toxin screening,
the sensor can significantly shorten a time for a clinical diagnostic, researcher added. However, the developed chip should go through a clinical trial for medical applications
#Crucial hurdle overcome in quantum computing: quantum logic gate in silicon built for the first time A team of Australian engineers has built a quantum logic gate in silicon for the first time,
making calculations between two qubits of information possible and thereby clearing the final hurdle to making silicon quantum computers a reality.
The significant advance, by a team at the University of New south wales (UNSW) in Sydney appears today in the international journal Nature. hat we have is a game changer,
said team leader Andrew Dzurak, Scientia Professor and Director of the Australian National Fabrication Facility at UNSW. ee demonstrated a two-qubit logic gate the central building block of a quantum computer and,
significantly, done it in silicon. Because we use essentially the same device technology as existing computer chips,
we believe it will be much easier to manufacture a full-scale processor chip than for any of the leading designs,
which rely on more exotic technologies. his makes the building of a quantum computer much more feasible,
since it is based on the same manufacturing technology as today computer industry, he added. The advance represents the final physical component needed to realise the promise of super-powerful silicon quantum computers,
which harness the science of the very small the strange behaviour of subatomic particles to solve computing challenges that are beyond the reach of even today fastest supercomputers.
In classical computers data is rendered as binary bits, which are always in one of two states:
0 or 1. However, a quantum bit (or ubit can exist in both of these states at once, a condition known as a superposition.
A qubit operation exploits this quantum weirdness by allowing many computations to be performed in parallel (a two-qubit system performs the operation on 4 values, a three-qubit system on 8, and so on.
f quantum computers are to become a reality, the ability to conduct one-and two-qubit calculations are said essential
Dzurak, who jointly led the team in 2012 that demonstrated the first ever silicon qubit,
also reported in Nature. Until now, it had not been possible to make two quantum bits alkto each other and thereby create a logic gate using silicon.
But the UNSW team working with Professor Kohei M. Itoh of Japan Keio University has done just that for the first time.
The result means that all of the physical building blocks for a silicon-based quantum computer have now been constructed successfully
allowing engineers to finally begin the task of designing and building a functioning quantum computer.""Despite this enormous global interest and investment, quantum computing has like Schrödinger cat been simultaneously possible (in theory)
but seemingly impossible (in physical reality), said Professor Mark Hoffman, UNSW's Dean of Engineering. he advance our UNSW team has made could,
we believe, be the inflection point that changes that Schrödinger paradigm, "he added.""The technology devised,
tested and patented by our team has the potential to take quantum computing across the threshold from the theoretical to the real.
and turned them into qubits. he silicon chip in your smartphone or tablet already has around one billion transistors on it,
with each transistor less than 100 billionths of a metre in size, said Dr Menno Veldhorst,
a UNSW Research Fellow and the lead author of the Nature paper. ee morphed those silicon transistors into quantum bits by ensuring that each has only one electron associated with it.
We then store the binary code of 0 or 1 on the pinof the electron, which is associated with the electron tiny magnetic field,
he added. Dzurak noted that the team had recently atented a design for a full-scale quantum computer chip that would allow for millions of our qubits,
all doing the types of calculations that wee just experimentally demonstrated"."He said that a key next step for the project is to identify the right industry partners to work with to manufacture the full-scale quantum processor chip.
Such a full-scale quantum processor would have major applications in the finance, security and healthcare sectors, allowing the identification
and development of new medicines by greatly accelerating the computer-aided design of pharmaceutical compounds (and minimising lengthy trial and error testing);
the development of new, lighter and stronger materials spanning consumer electronics to aircraft; and faster information searching through large databases e
#Detecting HIV diagnostic antibodies with DNA nanomachines A nanoscale machine composed of synthetic DNA can be used for the rapid,
sensitive and low-cost diagnosis of many diseases, including HIVNEW research may revolutionize the slow, cumbersome and expensive process of detecting the antibodies that can help with the diagnosis of infectious and autoimmune diseases such as rheumatoid arthritis and HIV.
An international team of researchers have designed and synthetized a nanometer scale DNA"machine "whose customized modifications enable it to recognize a specific target antibody.
Their new approach, which they described this month in Angewandte Chemie, promises to support the development of rapid,
low-cost antibody detection at the point-of-care, eliminating the treatment initiation delays and increasing healthcare costs associated with current techniques.
The binding of the antibody to the DNA machine causes a structural change (or switch),
which generates a light signal. The sensor does need not to be activated chemically and is rapid-acting within five minutes-enabling the targeted antibodies to be detected easily, even in complex clinical samples such as blood serum."
"One of the advantages of our approach is that it is said highly versatile Prof. Francesco Ricci, of the University of Rome, Tor Vergata, senior co-author of the study."
"This DNA nanomachine can be modified in fact custom so that it can detect a huge range of antibodies,
this makes our platform adaptable for many different diseases"."""Our modular platform provides significant advantages over existing methods for the detection of antibodies,"added Prof.
Vallée-Bélisle of the University of Montreal, the other senior co-author of the paper.""It is rapid,
does not require reagent chemicals, and may prove to be useful in a range of different applications such as point-of-care diagnostics and bioimaging"."
""Another nice feature of our this platform is said its low-cost Prof. Kevin Plaxco of the University of California, Santa barbara."
"The materials needed for one assay cost about 15 cents, making our approach very competitive in comparison with other quantitative approaches.""
""We are excited by these preliminary results, but we are looking forward to improve our sensing platform even more"said Simona Ranallo, a Phd student in the group of Prof.
Ricci at the University of Rome and first-author of the paper.""For example, we could adapt our platform
so that the signal of the nanoswitch may be read using a mobile phone. This will make our approach really available to anyone!
We are working on this idea and we would like to start involving diagnostic companies.""Image: The light-generating DNA antibody detecting nanomachine is illustrated here in action, bound to an antibody o
#Chemical process controls magnetism Magnets are well-known from the physics lessons at school, but they are covered hardly in chemistry lectures;
and it is still a chemical process by means of which researchers at Karlsruhe Institute of technology (KIT) have succeeded in controlling magnetic properties in bulk ferromagnets.
While physical processes may influence the orientation of the magnetic fields, the chemical process in this case controls magnetism in carefully chosen strongly ferromagnetic material systems.
The working principle used in this case is similar to the concept of lithium-ion batteries. There are several possibilities to create
or influence magnetism reversibly, by physical means. Standard methods are either to use a electromagnetic coil, for example,
where a high current produces a magnetic field, but the coil continuously consumes energy. Another possibility is to polarize the ferromagnet,
which means to align the magnetic structures in the material in parallel, such that an overall magnetic field is generated.
No energy is required for maintaining this magnetic field, but it is permanent and cannot easily be removed.
Another option is the magnetoelectric coupling, where an electric field is used to induce magnetism; however, this mechanism is limited often to the top monolayer of atoms of the crystal lattice only.
Hence, results in a minimal change in the magnetization. The newly developed chemical control of magnetism at KIT offers a unique approach that is beyond the concepts that are explained above:
The process influences the bulk material, not only the surface, and it is reversible, which means that it can be undone.
The distinct magnetic states (magnetic/nonmagnetic) are non volatile, which offer the major novelty that the different magnetic states unlike the electromagnetic coil can be maintained without requiring a continuous flow of current
and consumption of energy. housands of charge-discharge cycles of lithium-ion batteries used in mobile phones, for instance,
show that electrochemical processes can be highly reversible. This led us to the idea to exploit similar structures such as the lithium-ion batteries
says Subho Dasgupta of the KIT Institute of Nanotechnology. When charging and discharging a lithium-ion accumulator,
the ions migrate from one electrode to the other and intercalate into the electrode. The team of scientists around Dasgupta has produced now a lithium-ion accumulator, in
which one electrode is made of maghemite, a ferromagnetic iron oxide(?-Fe2o3), and the other electrode consists of pure lithium metal.
Experiments revealed that lithium ion intercalation in maghemite reduces its magnetization at room temperature. By the specific control of the lithium ions,
i e. by charging and discharging the accumulator, magnetization of maghemite can be controlled. Similar to conventional lithium-ion accumulators, this effect can be repeated.
In the experiments reported, the researchers reached a variation of magnetization by up to 30%.%In the long term, complete on
-and-off magnetic switching is the goal. The scientists hope to find a process to produce a magnetic switch that works according to the same principle as an electric transistor:
While the latter switches on-and-off a controlled current, the magnetic switch will switch on-and-off a strong ferromagnet.
In principle, this process may replace any applications, in which low-frequency electromagnets are used, but in this case can reach far higher energy efficiency.
Research of the KIT scientists mainly aims at small magnetic actuators for use in (micro) robots or microfluidics o
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