From Brookhaven : “DNA-Guided Assembly Yields Novel Ribbon-Like Nanostructures”

Brookhaven Lab

Approach could be useful in fabricating new kinds of materials with engineered properties

May 16, 2013
Contacts: Karen McNulty Walsh, (631) 344-8350 or Peter Genzer, (631) 344-3174

“Scientists at the U.S. Department of Energy’s Brookhaven National Laboratory have discovered that DNA “linker” strands coax nano-sized rods to line up in way unlike any other spontaneous arrangement of rod-shaped objects. The arrangement—with the rods forming “rungs” on ladder-like ribbons linked by multiple DNA strands—results from the collective interactions of the flexible DNA tethers and may be unique to the nanoscale. The research, described in a paper published online in ACS Nano, a journal of the American Chemical Society, could result in the fabrication of new nanostructured materials with desired properties.

DNA-tethered nanorods link up like rungs on a ribbonlike ladder—a new mechanism for linear self-assembly that may be unique to the nanoscale.
‘This is a completely new mechanism of self-assembly that does not have direct analogs in the realm of molecular or microscale systems,’ said Brookhaven physicist Oleg Gang, lead author on the paper, who conducted the bulk of the research at the Lab’s Center for Functional Nanomaterials (CFN).

Alexei Tkachenko, the CFN scientist who developed the theory to explain the exceptional arrangement, elaborated: ‘Remarkably, the system has all three dimensions to live in, yet it chooses to form the linear, almost one-dimensional ribbons. It can be compared to how extra dimensions that are hypothesized by high-energy physicists become hidden, so that we find ourselves in a 3-D world.’

Schematic of how gold nanorods link up when complementary strands of DNA attached to each rod (A, A’)—or DNA linker strands with ends complementary to two different types of DNA tethers on adjacent rods (B, C)—are used as “glue.”

See the full article here. There is much more.

One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.

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From Brookhaven Lab: “Multilayer Laue Lenses Enable Studies of Nanostructures with Ultra-high Resolution”

Brookhaven Lab

April 16, 2013
Angela Leroux-Lindsey

“Microscopes have been a centerpiece of experimental science since at least the 16th century, providing a window into the material world at extraordinarily small scales. As the structures examined decrease in size – some measuring just billionths of a meter – capturing an x-ray image at high spatial resolution while retaining sufficient imaging contrast becomes more difficult.

(a) Scanning electron microscope (SEM) image of the solid oxide fuel cell (SOFC) specimen adhered on a Si3Ni4 window with Pt welding. (b-d) are horizontal phase-gradient scanning x-ray microscope images obtained by differential intensity, moment analysis and Fourier-shift fitting algorithms, respectively. Artifacts and blurring effects can be seen in (b) and (c), as compared to (d). No image credit

One method of addressing this challenge is scanning x-ray microscopy, which uses a highly focused x-ray beam to produce spatial images of a specimen. In keeping with the scientific mission of Brookhaven National Laboratory’s National Synchrotron Light Source II (NSLS-II)., an advanced nanofocusing optic dubbed multilayer Laue lens (MLL) is being developed by the optics fabrication group for nanoscale imaging.”

See the full article here.

One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world.Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.

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From Argonne APS: “High-pressure imaging breakthrough a boon for nanotechnology”

News from Argonne National Laboratory

APRIL 9, 2013
Tona Kunz

“The study of nanoscale material just got much easier, and the design of nanoscale technology could get much more efficient, thanks to an advance in X-ray analysis.

Nanomaterials develop new physical and chemical properties, such as superconductivity and enhanced strength, when exposed to extreme pressure. A better understanding of how and when those changes occur can guide the design of better products that use nanotechnology.

But high-energy X-rays produced by lightsources such as the Advanced Photon Source (APS) at Argonne National Laboratory are the only way to study the in-situ structural changes induced by pressure in nanomaterials, and those studies have lacked precision.

Until now.

Bragg CXDI measurements were performed at 0.8, 1.7, 2.5, 3.2, and 6.4 GPa on the same crystal. The reconstructed images (both top and bottom views) are shown above. From W. Yang et al., Nat. Comm. 4 (2013).

As reported in a Carnegie Institute of Science press release, an international team of scientists using the APS detailed in the April 9 issue of the journal Nature Communications that they devised a way to overcome the distortion caused by sample environments used with the X-rays to improve spatial resolution imaging by two orders of magnitude. This 30-nanometer resolution greatly reduces uncertainties for studies of nanoscale materials. Researchers expect to fine-tune the technique to reach resolutions of a few nanometers in subsequent experiments.

The team, with members from the Carnegie Institution of Washington, the Center for High Pressure Science and Technology Advanced Research (P.R. China), Argonne National Laboratory, University College London (UK), and the Research Complex at Harwell (UK), found that by averaging the patterns of the bent waves—the diffraction patterns—of the same crystal using different sample alignments in the instrumentation, and by using an algorithm developed by researchers at the London Centre for Nanotechnology, they could compensate for the distortion and improve spatial resolution by two orders of magnitude. The new technique is called the “mutual coherent function” method, or MCF.”

See the Argonne article here. See the Argonne APS article here.

Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science

The Advanced Photon Source at Argonne National Laboratory is one of five national synchrotron radiation light sources supported by the U.S. Department of Energy’s Office of Science to carry out applied and basic research to understand, predict, and ultimately control matter and energy at the electronic, atomic, and molecular levels, provide the foundations for new energy technologies, and support DOE missions in energy, environment, and national security.

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From PNNL Lab: “A New Method for Measuring the Viscosity of Nanoparticles”

First direct determination of the chemical diffusivity and viscosity of secondary organic aerosols

March 2013
Suraiya Farukhi
Christine Sharp

“Results: For the first time, scientists measured the chemical diffusivity and viscosity of atmospheric organic particles, thanks to a new approach from scientists at Pacific Northwest National Laboratory, University of Washington, and Imre Consulting. The team doped atmospherically important organic nanoparticles, known as secondary organic aerosols (SOAs), with tracer molecules and measured their diffusion rate as they slowly worked their way out of the particles. Knowing the diffusion rate, the scientists calculated the particle’s viscosity.

‘Over the past two years, we have shown that long-standing assumptions about the most fundamental properties of SOA particles — phase and volatility — are wrong. Here, for the first time, we quantify chemical diffusivity in SOA particles and show that SOA viscosity is larger — a million times higher than assumed,’ said lead author Dr. Alla Zelenyuk, physical chemist at Pacific Northwest National Laboratory.

Determining the viscosity of tar-like secondary organic aerosols, ubiquitous atmospheric particles, is now possible thanks to a new method developed by scientists at Pacific Northwest National Laboratory, University of Washington, and Imre Consulting.

Why It Matters: Convenient, but unsubstantiated, assumptions have haunted atmospheric scientists studying SOAs for years, making it impossible to model how the particles affect climate and human health. With the development of new approaches and precise characterization instruments, scientists have disproved the common assumption. With this current study, Zelenyuk and her colleagues have given atmospheric modelers and others data that are invaluable for accurately portraying the particles and their effects in different scenarios, such as new regulations.”

See the full article here.

Pacific Northwest National Laboratory (PNNL) is one of the United States Department of Energy National Laboratories, managed by the Department of Energy’s Office of Science. The main campus of the laboratory is in Richland, Washington.

PNNL scientists conduct basic and applied research and development to strengthen U.S. scientific foundations for fundamental research and innovation; prevent and counter acts of terrorism through applied research in information analysis, cyber security, and the nonproliferation of weapons of mass destruction; increase the U.S. energy capacity and reduce dependence on imported oil; and reduce the effects of human activity on the environment. PNNL has been operated by Battelle Memorial Institute since 1965.

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From M.I.T.: “New solar-cell design based on dots and wires”

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MIT researchers improve efficiency of quantum-dot photovoltaic system by adding a forest of nanowires.

March 25, 2013
David L. Chandler

“Using exotic particles called quantum dots as the basis for a photovoltaic cell is not a new idea, but attempts to make such devices have not yet achieved sufficiently high efficiency in converting sunlight to power. A new wrinkle added by a team of researchers at MIT — embedding the quantum dots within a forest of nanowires — promises to provide a significant boost.”

Scanning Electron Microscope images show an array of zinc-oxide nanowires (top) and a cross-section of a photovoltaic cell made from the nano wires, interspersed with quantum dots made of lead sulfide (dark areas). A layer of gold at the top (light band) and a layer of indium-tin-oxide at the bottom (lighter area) form the two electrodes of the solar cell.
Images courtesy of Jean, et al/Advanced Materials

See the full article here.

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From SLAC: “X-ray Laser Explores New Uses for DNA Building Blocks”

March 11, 2013
Glenn Roberts Jr.

The founding father of DNA nanotechnology – a field that forges tiny geometric building blocks from DNA strands – recently came to SLAC to get a new view of these creations using powerful X-ray laser pulses.

For decades, Nadrian C. “Ned” Seeman, a chemistry professor at New York University, has studied ways to assemble DNA strands into geometric shapes and 3-D crystals with applications in biology, biocomputing and nanorobotics.

Nadrian C. “Ned” Seeman, chemistry professor at New York University.

He said the experiment conducted Feb. 7-11 at SLAC’s Linac Coherent Light Source enabled his team for the first time to study the DNA structures using smaller crystals in solution at room temperature.

They want to find out whether they can analyze the structure of their samples more precisely in this natural state, as their previous work relied on larger, frozen samples and the freezing process can damage the DNA structures.

A six-sided structure formed by DNA strands. Researchers studied DNA structures such as this in an experiment at SLAC’s Linac Coherent Light Source. (Credit: Nadrian C. Seeman; Nature 461, 74-77, 2009)

‘I think we’ll get some pretty exciting results,’ Seeman said during the last shift of the team’s LCLS experiment. ‘I’m very excited by everything I have seen so far.’”

See the full article here.

SLAC is a multi-program laboratory exploring frontier questions in photon science, astrophysics, particle physics and accelerator research. Located in Menlo Park, California, SLAC is operated by Stanford University for the DOE’s Office of Science.

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From Berkeley Lab: “Long Predicted Atomic Collapse State Observed in Graphene”

Berkeley Lab

Berkeley Lab researchers recreate elusive phenomenon with artificial nuclei

March 07, 2013
Lynn Yarris

“The first experimental observation of a quantum mechanical phenomenon that was predicted nearly 70 years ago holds important implications for the future of graphene-based electronic devices. Working with microscopic artificial atomic nuclei fabricated on graphene, a collaboration of researchers led by scientists with the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley have imaged the “atomic collapse” states theorized to occur around super-large atomic nuclei.

An artificial atomic nucleus made up of five charged calcium dimers is centered in an atomic-collapse electron cloud. (Image courtesy of Michael Crommie)

‘Atomic collapse is one of the holy grails of graphene research, as well as a holy grail of atomic and nuclear physics,’ says Michael Crommie, a physicist who holds joint appointments with Berkeley Lab’s Materials Sciences Division and UC Berkeley’s Physics Department. ‘While this work represents a very nice confirmation of basic relativistic quantum mechanics predictions made many decades ago, it is also highly relevant for future nanoscale devices where electrical charge is concentrated into very small areas.’”

Michael Crommie is a physicist who holds joint appointments with Berkeley Lab’s Materials Sciences Division and UC Berkeley’s Physics Department. (Photo by Roy Kaltschmidt)

See the full article here.

A U.S. Department of Energy National Laboratory Operated by the University of California

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From Stanford: “Stanford scientists fit light-emitting bioprobe in a single cell”

Stanford University

“Stanford researchers are the first to demonstrate that sophisticated light resonators can be inserted inside living cells without damage to the cell. The development marks a new age in which tiny lasers and light-emitting diodes yield new avenues in the study of living cells.

February 19, 2013
Andrew Myers

If engineers at Stanford have their way, biological research may soon be transformed by a new class of light-emitting probes small enough to be injected into individual cells without harm to the host.

This scanning electron microscope (SEM) image shows a nanobeam probe, including a large part of the handle tip, inserted in a typical cell. Gary Shambat, Stanford School of Engineering

Welcome to biophotonics, a discipline at the confluence of engineering, biology and medicine in which light-based devices – lasers and light-emitting diodes (LEDs) – are opening up new avenues in the study and influence of living cells.

The team described their probe in a paper published online Feb. 13 by the journal Nano Letters. It is the first study to demonstrate that tiny, sophisticated devices known as light resonators can be inserted inside cells without damaging the cell. Even with a resonator embedded inside, a cell is able to function, migrate and reproduce as normal.

Applications and implications

The researchers call their device a ‘nanobeam’, because it resembles a steel I-beam with a series of round holes etched through the center. This beam, however, is not massive, but measure only a few microns in length and just a few hundred nanometers in width and thickness. It looks a bit like a piece from an erector set of old. The holes through the beam act like a nanoscale hall of mirrors, focusing and amplifying light at the center of the beam in what are known as photonic cavities.

These are the building blocks for nanoscale lasers and LEDs.

‘Devices like the photonic cavities we have built are quite possibly the most diverse and customizable ingredients in photonics,’ said the paper’s senior author, Jelena Vuckovic, a professor of electrical engineering. ‘Applications span from fundamental physics to nanolasers and biosensors that could have profound impact on biological research.’”

See the full article here.

Leland and Jane Stanford founded the University to “promote the public welfare by exercising an influence on behalf of humanity and civilization.” Stanford opened its doors in 1891, and more than a century later, it remains dedicated to finding solutions to the great challenges of the day and to preparing our students for leadership in today’s complex world. Stanford, is an American private research university located in Stanford, California on an 8,180-acre (3,310 ha) campus near Palo Alto. Since 1952, more than 54 Stanford faculty, staff, and alumni have won the Nobel Prize, including 19 current faculty members

From PPPL: “Plasma meets nano at PPPL”

Princeton Plasma Physics Laboratory

John Greenwald
February 13, 2013

“Scientists at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) have launched a new effort to apply expertise in plasma to study and optimize the use of the hot, electrically charged gas as a tool for producing nanoparticles. This research aims to advance the understanding of plasma-based synthesis processes, and could lead to new methods for creating high-quality nanomaterials at relatively low cost.

Nanomaterials, which are measured in billionths of a meter, are prized for their use in everything from golf clubs and swimwear to microchips, paints and pharmaceutical products, thanks to their singular properties. These include exceptional strength and flexibility and high electrical conductivity. Carbon nanotubes, for example, are tens of thousands of times thinner than a human hair, yet are stronger than steel on an ounce-per-ounce basis.

Carbon nanotubes (NSF)

PPPL researchers have launched a nanotechnology laboratory that they envision as a step toward research capabilities that could serve as a resource for institutions and industries around the world. ‘It could be a test bed for new technologies and devices,’ said PPPL Deputy Director Adam Cohen. Users could include laboratories looking for small amounts of nanomaterial, ‘or companies interested in using plasmas in large-scale nanomanufacturing, or anyone in between.’”

Little is known about how low-temperature plasmas function as synthesizing material, said physicist Yevgeny Raitses, the principal investigator for nanoparticle research at PPPL. ‘We want to understand just what plasma does in order to use it in the best way possible, Raitses said.

Physicist Yevgeny Raitses, right, with Washington University undergraduate Mitchell Eagles in the PPPL nanolaboratory. (Photo credit: Elle Starkman/PPPL Office of Communications)

Discussions for the new PPPL laboratory began in 2009. ‘The question I always had,’ recalled Deputy Director Cohen, ‘is that if nanoparticles and nanotubes are going to be in everything from car cylinders to medical equipment to nano-robots, who’s going to ensure that these materials are made consistently with the highest quality? That seemed like an opportunity for us.’”

See the full February 13, 2013 article here. But see a fuller October 22, 2012 version AT DOE Pulse. Kinda makes one wonder who is minding the public image effort at PPPL.

Princeton Plasma Physics Laboratory is a U.S. Department of Energy national laboratory managed by Princeton University.

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From SLAC: “For Superionic Material, Smaller is Better”

SLAC National Accelerator Laboratory

Mike Ross
February 7, 2013

“A material that could enable faster memory chips and more efficient batteries can switch between high and low ionic conductivity states much faster than previously thought, SLAC and Stanford researchers have determined. The key is to use extremely small chunks of it.

‘Our result is a step toward using this material, copper sulfide, in low-cost solid-state electrical batteries,’ said the leader of the research team, Aaron Lindenberg, of the Stanford Institute for Materials and Energy Sciences and the Stanford PULSE Institute. The institutes are run jointly by SLAC and Stanford.

‘For the first time, we’ve seen the atomic-scale details of exactly how these nanoscale materials transform, or switch, from a state that is poorly conducting to one that is highly conducting,’ he said. ‘And what we’ve learned gives us confidence about our ability to tune its structure and properties to be useful in new technologies.’

Lindenberg’s team reported its results last month in Nature Communications.”

See the full article here.

SLAC National Accelerator Laboratory is home to a two-mile linear accelerator—the longest in the world. Originally a particle physics research center, SLAC is now a multipurpose laboratory for astrophysics, photon science, accelerator and particle physics research.

SLAC is a multi-program laboratory exploring frontier questions in photon science, astrophysics, particle physics and accelerator research. Located in Menlo Park, California, SLAC is operated by Stanford University for the DOE’s Office of Science.

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