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

Scientists from the University of California, Berkeley; the University of California, Santa Cruz; Harvard University; the University of Manchester in the United Kingdom; and the National Institute for Materials Science in Tsukuba, Japan, have conducted an experiment that confirms a theory first put forth 40 years ago stating that electrons confined in quantum space would move along common paths rather than producing a chaotic jumble of trajectories. To conduct this experiment, the scientists combined advanced imaging techniques and precise control over electron behavior within graphene, a two-dimensional material made of carbon atoms. The scientists used the finely tipped probe of a scanning tunneling microscope to first create a trap for electrons and then hover close to a graphene surface to detect electron movements without physically disturbing them. 

Researchers from North Carolina State University and Iowa State University have demonstrated a new technique for self-assembling electronic devices. The proof-of-concept work was used to create nanoscale and microscale diodes and transistors, and paves the way for self-assembling more complex electronic devices without relying on existing computer chip manufacturing techniques. The self-assembling technique follows a multistep process that makes use of liquid metal particles and a solution that contains molecules called ligands that are made up of carbon and oxygen. At some point during this process, the metal ions interact with the oxygen to form semiconductor metal oxides, while the carbon atoms form graphene sheets. These ingredients assemble themselves into a well-ordered structure consisting of semiconductor metal oxide molecules wrapped in graphene sheets. 

Researchers from the University of North Carolina Charlotte and the U.S. Department of Energy’s Brookhaven National Laboratory have developed an innovative computational framework for modeling multifunctional RNA nucleic acid nanoparticles. By integrating small and wide-angle x-ray scattering data with data-driven molecular dynamics simulations, the researchers developed a methodology for studying multistranded RNA nucleic acid nanoparticles in their solution-state environments. Small-angle x-ray scattering–Molecular Dynamics (SAXS–MD) guides simulations toward biologically meaningful conformations, addressing the limitations of traditional unconstrained molecular dynamics simulations.

Scientists from Clark Atlanta University and the Molecular Foundry at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory have discovered a faster, more sustainable method for making metal-encapsulated covalent organic frameworks – materials that have the potential to play a crucial role in catalysis, energy storage, and chemical sensing. The new one-step, room-temperature process eliminates the need for toxic solvents and significantly reduces the production time from several days to just one hour. The covalent organic frameworks were evaluated to see how porous and crystalline they are and how much metal was added to the structure. Also, powerful transmission electron microscopes were used to visualize the covalent organic framework structure and the distribution of metal throughout.

Researchers at Rice University have developed an innovative imaging platform that promises to improve our understanding of cellular structures at the nanoscale. This platform offers significant advancements in super-resolution microscopy, enabling fast and precise three-dimensional (3D) imaging of multiple cellular structures. By integrating an angled light sheet, a nanoprinted microfluidic system, and advanced computational tools, the platform significantly improves imaging precision and speed, allowing for clearer visualization of how different cellular structures interact at the nanoscale.

Rice University scientists have developed halide perovskite nanocrystals that have shown potential as antimicrobial agents that are stable, effective, and easy to produce. The scientists developed a method that coated the halide perovskite nanocrystals in two layers of silicon dioxide. Next, they tested the antimicrobial properties and durability of the double-coated halide perovskite nanocrystals and showed that under relatively low levels of visible light, the halide perovskite nanocrystals destroyed more than 90% of E. coli bacteria in a solution after six hours. 

Nanoparticles have transformed how mRNA vaccines and therapeutics are delivered by allowing them to travel safely through the body, reach target cells and release their contents efficiently. At the heart of these nanoparticles are ionizable lipids, special molecules that can switch between charged and neutral states depending on their surroundings. Now, researchers at the University of Pennsylvania have used an iterative process to find the ideal structure for the ionizable lipid. By borrowing the idea of directed evolution, a technique used in both chemistry and biology that mimics the process of natural selection, the researchers combined precision with rapid output to achieve their ideal “ionizable lipid recipe."

Researchers at Rice University have found a new way to improve a key element of thermophotovoltaic  systems, which convert heat into electricity via light. Using an unconventional approach inspired by quantum physics, the researchers designed a thermal emitter that can deliver high efficiencies within practical design parameters. The emitter is composed of a tungsten metal sheet, a thin layer of a spacer material and a network of silicon nanocylinders. The research could inform the development of thermal-energy electrical storage, which holds promise as an affordable, grid-scale alternative to batteries.

During a NASA microgravity flight, researchers from Iowa State University and the University of Wisconsin-Madison have tested how a printer would work in the zero gravity of space. The ink used in this printer featured silver nanoparticles made with biobased polymers. The printer uses a 3D printing process that jets ink under an electric field, which could eliminate the need for gravity to help deposit ink. If the technology used in this printer works in zero gravity, astronauts could use such a printer to make electric circuits for spacecraft or equipment repairs or to manufacture high-value electronic components.

Researchers from the University of Mississippi have shown that using glycopolymers – polymers made with natural sugars like glucose – to coat nanoparticles that deliver cancer-fighting medication directly to tumors reduces the body's immune response to cancer treatment. The researchers tested glycopolymer-coated nanoparticle treatments in mice with breast cancer and found that more nanoparticles reached the tumors in the glycopolymer treatment compared to more conventional treatment that uses polyethylene glycol-based nanoparticles. "Our findings highlight that the nanoparticles we're using significantly reduce unwanted immune responses while dramatically enhancing drug delivery, both in cell and animal models,” said Kenneth Hulugalla, one of the scientists involved in this study.