News from the NNI Community - Research Advances Funded by Agencies Participating in the NNI

By offering cells a "tightrope," scientists from Johns Hopkins University and Virginia Tech have discovered a new and surprising form of cellular movement. Normally, when cells crawling in an organism come into contact, they reverse and move randomly away from one another. But when nanofiber "tightropes" coated with proteins were suspended in a three-dimensional medium for cells to explore, cells either walked past each other to avoid a collision or formed a train moving together along the length of the nanofiber. This new understanding of cellular movement helps explain why some drugs work differently in tests within petri dishes than they do in humans or animals.

A team of nanobiotechnologists at Harvard's Wyss Institute for Biologically Inspired Engineering and the Dana-Farber Cancer Institute has devised a programmable DNA self-assembly strategy that solves the key challenge of robust nucleation control and paves the way for applications such as ultrasensitive diagnostic biomarker detection and scalable fabrication of micrometer-sized structures with nanometer-sized features. Using the method, called “crisscross polymerization,” the researchers can initiate weaving of nanoribbons from elongated single strands of DNA by a seed-dependent nucleation event. 

A team of scientists at the University of Massachusetts Amherst has developed the thinnest and most sensitive flow sensor, which could have significant implications for medical research and applications. The new flow sensor is based on graphene, a single layer of carbon atoms arranged in a honeycomb lattice, to pull in charge from continuous aqueous flow. This phenomenon provides an effective flow-sensing strategy that is self-powered and delivers key performance metrics higher than other electrical approaches by hundreds of times.

Researchers at the University of Illinois Urbana-Champaign have developed a fast, low-cost technique to see and count viruses or proteins from a sample in real time, without any chemicals or dyes. In optical microscopes, light bounces off any molecules or viruses it encounters on a slide, creating a signal. Instead of a regular glass slide, this technique uses a nanostructured glass surface that reflects only one wavelength of light. The technique could underpin a new class of devices for rapid diagnostics and viral load monitoring, including HIV and the virus that causes COVID-19.

A team of researchers at Northwestern University has developed a nanoscale tandem catalyst to get more propylene out of propane during dehydrogenation. The researchers developed a tandem reaction to reduce the number of steps required to produce propylene during dehydrogenation of propane, and in so doing, have increased yield. Propylene is a gaseous hydrocarbon that is used to make several types of polymers.

A research team led by Brown University physicists has found a new way to precisely probe the nature of the superconducting state in magic-angle graphene. The technique enables researchers to manipulate the repulsive force between elections – the Coulomb interaction – in the system. The researchers show that magic-angle superconductivity grows more robust when Coulomb interaction is reduced, an important piece of information in understanding how this superconductor works.

In recent years, it was thought that the pace had slowed; one of the biggest challenges of putting more circuits and power on a smaller chip is managing heat. Now, a multidisciplinary group that includes scientists from the University of Virginia and Northwestern University is inventing a new class of material with the potential to keep chips cool as they keep shrinking in size – and to help Moore's Law remain true. 

Physicists at Rice University have found a way to boost the light from a nanoscale device more than 1,000 times greater than they anticipated. When looking at light coming from a plasmonic junction – a microscopic gap between two gold nanowires – there are conditions in which applying optical or electrical energy individually prompt a modest amount of light emission. The physicists discovered that applying the optical and electrical energies together caused a burst of light that far exceeded the output under either individual energy. The effect could be used to make advanced photocatalysts and nanophotonic switches for computer chips.

Engineers at Duke University are leading a nationwide effort – which also includes the California Institute of Technology, City University of New York, Harvard University, Stanford University, and the University of Pennsylvania – to develop a "super camera" that captures just about every type of information that light can carry, such as polarization, depth, phase, coherence, and incidence angle. The new camera will also use edge computing and hardware acceleration technologies to process the vast amount of information it captures within the device in real-time. The imaging side of the technology will be based on optical metasurfaces – ultra-thin devices that are composed of arrays of subwavelength nanostructures.

Physicists from Michigan Technological University have explored alternative materials to improve the capacity and shrink the size of digital data storage technologies. The team found that chromium-doped nanowires with a germanium core and silicon shell can be an antiferromagnetic semiconductor, which opens up possibilities for smaller and smarter electronics with higher capacity data storage and manipulation.