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

Scientists from Oregon State University and Oregon Health and Science University have developed an approach involving nanoparticles, photoacoustic imaging and infrared light works that may offer a better, safer way to diagnose and treat ectopic pregnancies. To test if their new concept might improve ectopic pregnancy detection and treatment, the researchers injected a non-toxic solution containing nanoparticles and a light-responsive agent into pregnant mice. The solution traveled with the bloodstream until it concentrated on the surface of the placenta. Next, the researchers placed their imaging device outside the mouse’s body, and pointed it toward the mouse’s uterus. The resulting images clearly showed the placenta’s surface was lit up by nanoparticles. 

Scientists at the U.S. Department of Energy's Argonne National Laboratory and Old Dominion University have created a novel testbed to explore the behavior of electrons in a special class of materials called topological insulators, which could see applications in quantum computing. Electrons on the surface of topological insulators can exist in states that allow them to flow with almost no resistance. In previous work, graphene nanoribbons – small strips of graphene, a one-atom-thick sheet of carbon atoms – were shown to exhibit promising topological states. Inspired by this work, the researchers created an artificial graphene testbed to further explore these topological effects.

Researchers from Southern Methodist University in Dallas and Applied Research Associates in Albuquerque have demonstrated, for the first time, that certain chemical coatings can alter their swimming propulsion within biological fluids when applied to #microparticles and #nanoparticles. Coated particles were suspended in mucus synthesized from pig stomach and navigated with rotating magnetic fields. The surface coatings altered the propulsion behavior of the particles, depending on both magnetic field properties and localized mucus properties.

Biomedical engineers at Duke University have developed a tablet-based vaccine for urinary tract infections (UTIs) that rapidly dissolves when placed under the tongue. The vaccine consists of mucus-penetrating peptide-polymer nanofibers that can elicit antibody responses systemically and in the urogenital tract. In a mouse model of UTI, the researchers demonstrated equivalent efficacy to high-dose oral antibiotics – the current standard for UTI treatments – but with significantly less perturbation of the gut microbiome.

Nearly a decade ago, in collaboration with the Indian government, the National Institute of Biomedical Imaging and Bioengineering (which is part of the National Institutes of Health) spearheaded an international effort to develop a wearable cuffless system. Building on years of research, scientists from The University of Texas at Austin and Texas A&M University are now fine-tuning such a device. Made of graphene, one of the thinnest materials in the world, the device is worn on the underside of the wrist and can measure blood pressure with comparable accuracy to a standard blood pressure cuff. 

Two-dimensional materials can be packed together more densely than conventional materials, so they could be used to make transistors, but one issue holding back these next-generation electronics is the heat they generate when in use and the fact that scientists don't have a good understanding of how 2D materials expand when temperatures rise. Now, researchers from the Massachusetts Institute of Technology and Southern University of Science and Technology in China have demonstrated that they can use laser light to track vibrations of the atoms that comprise 2D materials, allowing the researchers to accurately extract the materials’ thermal expansion coefficients.

Researchers from Rice University, the University of Calgary, the University of Washington, and the South Dakota School of Mines and Technology have used Rice University's unique flash Joule heating process to convert asphaltenes, a byproduct of crude oil production, instantly into turbostratic (loosely aligned) graphene and mix it into composites for thermal, anti-corrosion and 3D-printing applications. The process makes good use of material otherwise burned for reuse as fuel or discarded into tailing ponds and landfills. 

Researchers at the U.S. Department of Energy’s Brookhaven National Laboratory have developed a new way to guide the self-assembly of a wide range of novel nanoscale structures using simple polymers as starting materials. Under an electron microscope, these nanometer-scale structures look like tiny Lego building blocks, including parapets for miniature medieval castles and Roman aqueducts. The work could help guide the design of custom surface coatings with tailored optical, electronic, and mechanical properties, for use in sensors, batteries, and filters.

Researchers at Stanford University have developed a new material for printing at the nanoscale and used it to print minuscule lattices that are both strong and light. The researchers demonstrated that the new material can absorb twice as much energy than other 3D-printed materials of comparable density. In the future, their invention could be used to create better lightweight protection for fragile pieces of satellites, drones, and microelectronics.

Researchers at the National Institute of Standards and Technology have created grids of tiny clumps of atoms known as quantum dots and studied what happens when electrons dive into these nanoparticles. The researchers made multiple 3-by-3 grids of precisely spaced quantum dots, each comprising one to three phosphorus atoms. Attached to the grids were electrical leads and other components that enabled electrons to flow through them. The grids provided playing fields in which electrons could behave in nearly ideal, textbook-like conditions, free of the confounding effects of real-world materials.