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

Researchers at the University of Chicago have found that a sheet of glass crystal just a few atoms thick could trap and carry light. This discovery demonstrates what are essentially 2D photonic circuits. Photonic circuits already exist, but they are larger and three-dimensional, and particles of light, or photons, travel enclosed inside the waveguides used in these circuits. (Waveguides act like the wires that are used to carry electrical signals, but they carry photons instead.) With this system, the glass crystal is thinner than a photon – so, part of a photon actually sticks out of the crystal, as it travels. This work made use of the fabrication facilities of the Pritzker Nanofabrication Facility at the University of Chicago, which receives support from SHyNE Resource, a node of the National Nanotechnology Coordinated Infrastructure.

In rooms where smoking has taken place regularly, tobacco's imprint lingers on indoor surfaces, even long after regular smoking has stopped. The leftover residues, known as thirdhand smoke, can be a long-term source of indoor pollutants. Now, researchers from the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab), the University of California Berkeley, the University of California Riverside, and San Diego State University, have examined smoke-contaminated aged carpets and new carpets exposed to fresh smoke in the lab and found that carpets can be an important reservoir and source of contaminants from thirdhand smoke. The work was carried out at Berkeley Lab’s Air Quality Testing Laboratory and the Molecular Foundry, a user facility at Berkeley Lab. 

Researchers from the University of Missouri have developed a new method using nanopores – nanometer-sized holes – to help scientists advance their discoveries in neuroscience. "Potential applications include studying the structures of DNA- and RNA-based diseases and disorders,” said Li-Qun "Andrew" Gu, one of the scientists involved in this study. “Or we could potentially discover new small-molecule drug compounds that can be used in future drug discoveries."

Scientists from Rice University, Cornell University, the Army Research Laboratory, the Naval Research Laboratory, and the Indian Institute of Technology Kanpur mixed hexagonal boron nitride – a soft variety also known as "white graphite" – with cubic boron nitride – a material second to diamond in hardness – and found that the resulting nanocomposite interacted with light and heat in unexpected ways that could be useful in next-generation microchips and quantum devices. "What is fascinating about this study is that it opens up possibilities to tailor boron nitride materials with the right amounts of hexagonal and cubic structures, thus enabling a broad range of tailored mechanical, thermal, electrical, and optical properties in this material," said Pulickel Ajayan, one of the scientists involved in this study.

Engineers at Johns Hopkins University have developed nanoscale tattoos – dots and wires that stick to live cells, while flexing and conforming to the cells' wet and fluid outer structure. "If you imagine where this is all going in the future, we would like to have sensors to remotely monitor and control the state of individual cells and the environment surrounding those cells in real time," said David Gracias, the engineer who led the development of this technology. "If we had technologies to track the health of isolated cells, we could maybe diagnose and treat diseases much earlier and not wait until the entire organ is damaged."

Researchers from Penn State, Western Michigan University, and the U.S. Department of Energy’s Oak Ridge National Laboratory have found that atomic-scale steps on sapphire substrates enable crystal alignment of 2D materials during semiconductor fabrication. They also discovered that manipulation of these materials during synthesis may reduce defects and improve electronic device performance.

Researchers at the Children's Hospital of Philadelphia and the Perelman School of Medicine at the University of Pennsylvania have developed a proof-of-concept model for delivering gene-editing tools to treat blood disorders. Their approach uses mRNA encapsulated in lipid nanoparticles as a technology platform to carry out in vivo cellular reprogramming, modifying diseased blood cells directly within the body. Use of this platform in clinical settings could expand access and reduce the cost of gene therapies for blood disorders, many of which currently require chemotherapy and a stem cell transplant.

Researchers at Vanderbilt University have shown that a type of engineered nanostructured surface can be used to trap micrometer and sub-micrometer particles within seconds. The researchers state that the enhanced absorption of light in the nanostructures helps in the transport of analytes to biosensing surfaces and could help in the detection of cancer.

Researchers from Columbia University, the University of Connecticut, and the Center for Functional Nanomaterials at the U.S. Department of Energy’s Brookhaven National Laboratory have built a structure out of DNA and then coated it with glass, creating a very strong material with very low density. The glass coated only the strands of DNA, leaving a large part of the material volume as empty space, much like the rooms within a house or building. The DNA skeleton reinforced the thin, flawless coating of glass, making the material strong, and the voids constituting most of the material's volume made it lightweight. Such glass nanolattice structures have four times higher strength but five times lower density than steel. 

For nearly 20 years, scientists have known that some DNA-stabilized nanometer-sized clusters of silver atoms glow visibly in red and green, making them useful in a variety of chemical and biosensing applications. Now, researchers from the University of California, Irvine; the University of Jyväskylä in Finland; the University of Copenhagen in Denmark; and Sophia University in Tokyo, Japan, are using machine learning to determine what part of the DNA sequence is correlated to the different fluorescence colors of the nanoclusters. In particular, they are looking for DNA-stabilized silver nanoclusters that would emit near-infrared light, enabling researchers to see through living cells and centimeters of biological tissue.