Lifeboat Foundation

Researchers at the Technical University of Munich (TUM) have developed the world’s first electric nanomotors made of DNA. The self-assembling structures can be activated by an electric charge to spin a ratcheting rotor arm.

The tiny motor was made using a technique called DNA origami. Like its namesake papercraft, the method involves intricately folding strands of DNA into three-dimensional shapes, with past examples including virus traps, immune-evading drug delivery systems, and even microscopic Van Gogh replicas. These structures are made by carefully selecting DNA sequences that will fold and attach to each other in certain ways, so researchers can add specific strands to a solution and let the DNA objects assemble themselves.

For the new study, the team used this process to make a molecular motor out of DNA for the first time. The motor consists of a rotor arm measuring up to 500 nanometers (nm) long, which is mounted on a base about 40 nm high that’s fixed to a glass plate. Wrapped around the tip of the base, just below the rotor, is a platform with several ratcheting obstacles built into its surface, which controls the direction that the rotor can spin.

In what’s being hailed as an important first for chemistry, an international team of scientists has developed a new technology that can selectively rearrange atomic bonds within a single molecule. The breakthrough allows for an unprecedented level of control over chemical bonds within these structures, and could open up some exciting possibilities in what’s known as molecular machinery.

Molecules are made up of clusters of atoms, and are the product of the nature and arrangement of those atoms within. Where oxygen molecules we breathe feature the same repeating type of atom, sugar molecules are made of carbon, oxygen and hydrogen.

Scientists have been pursuing something called “selective chemistry” for some time, with the objective of forming exactly the type of chemical bonds between atoms that they want. Doing so could lead to the creation of complex molecules and devices that can be designed for specific tasks.

A nanoscale rotary motor made of DNA origami, driven by ratcheting and powered by an external electric field, shows the ability to wind up a spring and has mechanical capabilities approaching those of biological motors.

New electrocatalysis electrodes have been created that are simpler and cheaper than conventional ones, and can substantially increase the efficiency of water splitting. Decorated with chiral molecules like helicenes, these devices double the activity of the oxygen evolution reaction, the bottleneck of the process, and improve its selectivity.

‘With electrocatalysis, we [can] use electrons from renewable sources [like solar and wind] to produce clean chemicals and fuels,’ explains Magalí Lingenfelder from the Max Planck–EPFL laboratory for molecular nanoscience and technology, in Switzerland, who led the study. In this work, her team focused on the oxygen evolution reaction. ‘It’s the bottleneck of water splitting,’ she says. ‘We wanted to increase its performance with cheap, simple solutions.’

Metamaterial Space Applications:

In this presentation I will talk about nanophotonics, more specifically metasurfaces – subwavelength patterned surfaces – and explain how this can be used for space applications. As recently displayed by the stunning images from the James Webb space telescope, we often rely on recording the intensity of light (e.g. with a camera) to study the universe. However, light fundamentally has several additional degrees of freedom which can carry information, e.g. polarization, phase, and spectral content. While it is true that many conventional optical components can address these degrees of freedom individually (e.g., polarizers, phase retarders, and filters), metasurfaces enable general manipulations of phase, amplitude, and polarization on the nanoscale, thereby providing ample opportunity to create new versions of existing components and even enable functionality not possible using conventional technologies. In the presentation I will cover several examples of metasurfaces I have been working on and explain their relevance for space applications. I will attempt to explain the working principles, why metasurfaces can be useful, as well as how we fabricate metasurfaces in a cleanroom.

About the speaker: Dr. Tobias Wenger is a postdoc at JPL’s microdevices laboratory (MDL) where his main efforts relate to nanophotonics — light at the nanoscale – and how we can engineer structures and components in order to control light in new ways. Tobias received his PhD from Chalmers University of Technology, Sweden, where he worked on understanding the physical properties of plasmons in graphene.

At JPL, Tobias is applying his knowledge of subwavelength electromagnetics to design metasurface-based optical components, mainly for infrared wavelengths. Metasurfaces are a novel approach to optics which uses subwavelength elements for controlling the phase, amplitude and polarization of transmitted and/or reflected electromagnetic radiation. Tobias research interests intersect optics, computational electromagnetics, and microfabrication and he enjoys both the practical and theoretical aspects of this work. During his postdoc time at MDL, he has worked on metasurface-based optical concentrators, IR detectors, plasmonic filters, wavefront sensing, and grating replication.

A space elevator, a technology connecting the Earth’s surface to a space station, would allow for the cost-efficient transport of people and materials. However, a very light yet strong material is essential to making such a technology a reality.

The carbon nanotube is a material that is 100 times stronger, yet four times lighter, than steel, with copper-like high electrical conductivity and diamond-like thermal conductivity. However, previous carbon nanotube fibers were not ideal for extensive use, owing to the small contact area with adjacent carbon nanotubes and limited length they possessed.

Figure 1. Schematic of the structural changes of carbon nanotubes at different annealing temperatures. (Image: Korea Institute of Science and Technology)

In a new paper in PNAS, “Triplet-Pair Spin Signatures From Macroscopically Aligned Heteroacenes in an Oriented Single Crystal,” National Renewable Energy Laboratory (NREL) researchers Brandon Rugg, Brian Fluegel, Christopher Chang, and Justin Johnson tackle one of the fundamental problems in quantum information science: how to produce pure elements of quantum information—that is, those that start and remain in a well-defined “spin state”—at practical temperatures.

Quantum information science has the potential to revolutionize computation, sensing, and communications. But many of these applications are still beyond reach because of the challenges of producing units of quantum information, or qubits, without relying on extremely low temperatures to maintain their purity. Current approaches to identifying suitable quantum materials tend to rely on trial and error.

“The field of developing new molecules and materials [for quantum information science] sometimes progresses through ad hoc methods and serendipity. ‘This material just so happens to work better than the other one’—we saw a lot of that happening, and decided ultimately that it was not going to suffice for a project where the goal was to limit the set of possible options,” said Justin Johnson, a researcher in NREL’s Chemistry and Nanoscience Center. “We wanted to have the theory provide us with firm guidelines about what should happen.”

Australian scientists say they’ve made a “eureka moment” breakthrough in gas separation and storage that could radically reduce energy use in the petrochemical industry, while making hydrogen much easier and safer to store and transport in a powder.

Nanotechnology researchers, based at Deakin University’s Institute for Frontier Materials, claim to have found a super-efficient way to mechanochemically trap and hold gases in powders, with potentially enormous and wide-ranging industrial implications.

Mechanochemistry is a relatively recently coined term, referring to chemical reactions that are triggered by mechanical forces as opposed to heat, light, or electric potential differences. In this case, the mechanical force is supplied by ball milling – a low-energy grinding process in which a cylinder containing steel balls is rotated such that the balls roll up the side, then drop back down again, crushing and rolling over the material inside.

Researchers at Rice University have shown how they can hack the brains of fruit flies to make them remote controlled. The flies performed a specific action within a second of a command being sent to certain neurons in their brain.

The team started by genetically engineering the flies so that they expressed a certain heat-sensitive ion channel in some of their neurons. When this channel sensed heat, it would activate the neuron – in this case, that neuron caused the fly to spread its wings, which is a gesture they often use during mating.

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