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

Researchers at Texas A&M University have described how certain minerals can regulate gene expression, thus controlling the number of proteins made by a cell and encouraging tissue regeneration. The researchers introduced a new class of mineral-based nanoparticles, called nanosilicates, to direct human stem cells toward bone cells. Nanosilicates are disc-shaped mineral nanoparticles 20-30 nanometers in diameter and 1-2 nm in thickness that are highly biocompatible and are readily eaten up by cells. Once inside a cell, the nanoparticles slowly dissolve into individual minerals, which turn "on” a set of key genes that instruct the cell to take on specific functions, such as converting into another type of cell.

Researchers from Tulane University have developed a new family of two-dimensional (2D) materials that could be used in advanced electronics and high-capacity batteries. The new family of 2D materials, called transition metal carbo-chalcogenides, combines the characteristics of two other families of 2D materials – transition metal carbides and transition metal dichalcogenides.

Twisted bilayer graphene, made of two sheets of graphene twisted to a specific "magic" angle, has been shown to have superconductivity, meaning that it can conduct electricity with very little resistance. But using this approach to make devices remains challenging because of the low yield of fabricating twisted bilayer graphene. Now, researchers at the University of Pennsylvania have shown how patterned, periodic deformations of a single layer of graphene transforms it into a material with electronic properties previously seen in twisted graphene bilayers. Through a better understanding of how unique properties occur when single sheets of graphene are subjected to periodic strain, this work could create quantum devices, such as orbital magnets and superconductors, in the future. 

Researchers at Rice University have created a potentially disruptive technology for the ultraviolet optics market. By precisely etching hundreds of tiny nanotriangles on the surface of a microscopic film of zinc oxide, nanophotonics pioneer Naomi Halas and colleagues have created a "metalens" that transforms incoming long-wave ultraviolet A radiation into a focused output of vacuum ultraviolet radiation. This type of radiation is used in semiconductor manufacturing, photochemistry, and materials science and has historically been costly to work with, in part because it is absorbed by almost all types of glass used to make conventional lenses.

Researchers at the U.S. Department of Energy’s Sandia National Laboratories have developed a nanocomposite coating that could be used in many applications, such as shielding in the form of mechanical barriers, body armor, and space debris shields. The coating is composed of thin layers of carbon black interspersed between slightly thicker layers of silica, and it looks like the layering of a seashell, each layer helping the next to contain and mitigate shock.

Researchers at the University of Alabama at Birmingham have developed a novel therapy that improves obesity and Type 2 diabetes conditions of mice that were fed a high-fat diet. The therapy acts through sustained release of nitric oxide, a gas that relaxes the inner muscles of blood vessels. The researchers used a nanomatrix gel composed of peptide-based molecules that self-assemble into cylindrical micelle nanofibers. The nanomatrix gel can release a burst of nitric oxide in the first 24 hours, followed by sustained nitric oxide release for four weeks. At the end of 12 weeks, the nitric oxide-mice had gained 17% less body weight, compared to controls, and that weight difference was due mainly to decreased fat.

Researchers have routinely studied DNA and protein molecules by turning them into regularly packed crystals that can be examined with an X-ray beam or radio waves. However, these techniques cannot be applied to RNA molecules with nearly the same effectiveness, because their molecular composition and structural flexibility prevent them from easily forming crystals. Now, researchers from the Wyss Institute for Biologically Inspired Engineering at Harvard University and Harvard Medical School have reported a new approach to the structural investigation of RNA molecules. This approach uses an RNA nanotechnological technique that allows multiple identical RNA molecules to be assembled into a highly organized structure. 

Researchers from Rice University, Arizona State University, and the U.S. Department of Energy’s Pacific Northwest National Laboratory have developed a high-performance catalyst that can, with near 100% efficiency, pull ammonia from low levels of nitrates that are widespread in industrial wastewater and polluted groundwater. The researchers showed that the catalyst, which was made by dispersing ruthenium atoms into a copper nanowire matrix, converts nitrate levels of 2,000 parts per million into ammonia, followed by an efficient gas stripping process for ammonia product collection.

Researchers from Michigan State University and the Max Planck Institute of Molecular Plant Physiology in Germany have repurposed bacterial microcompartments (each about 40 nanometers in diameter) and programmed them to produce valuable chemicals from inexpensive starting ingredients. The researchers engineered the microcompartments to turn the simple and inexpensive compounds formate and acetate into pyruvate, bringing enzymes and these compounds together in the same, smaller space, rather than having them spread out throughout a bacterial cell.

Scientists from the U.S. Department of Energy’s Lawrence Berkeley National Laboratory and three German universities (Technische Universitat Bergakademie Freiberg, Universitat Hamburg, and Technische Universitat Munchen) have found a way to track electrons along their round trip from molecules to nanoparticles in materials that convert sunlight into electricity or fuels. The scientists found that a common nanoparticle material, zinc oxide, first stalls the electrons for a while and then lets the electrons move along the surface of the nanoparticles. This makes it likely that the charges can get lost or can damage the nanoparticle material. The ability to reveal these bottlenecks for electron travel will help researchers design better materials for turning sunlight into other forms of energy.