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

Researchers from the University of Texas at Dallas, the Massachusetts Institute of Technology, and international collaborators have found that rhombohedral graphene behaves similarly to semiconductors and exhibits novel magnetism and superconductivity, as well as the quantum anomalous Hall effect, at extremely low temperatures. Graphene – a single layer of carbon atoms arranged in a flat honeycomb pattern – can be stacked in two different ways: Hexagonal stacking occurs when even-numbered graphene layers are aligned (with the odd-numbered layers rotated 60 degrees relative to the even layers); in contrast, rhombohedral stacking features a unidirectional 60-degree rotation for each successive layer.

Researchers from the University of Connecticut will grow rod-shaped nanoparticles, called Janus base nanotubes, on the International Space Station. These nanotubes will carry interleukin-12, a protein produced naturally by the human body to stimulate the development of helper T-cells, immune cells known for killing pathogens and cancer cells. With cross sections of just 20 nanometers, the nanotubes can slip into the cracks and attack solid tumors from the inside and then release interleukin-12 inside a tumor. Manufacturing these nanotubes in space has many advantages. “Since our nanotubes are self-assembled, there is a lot of similarity to crystallization,” says Yupeng Chen, one of the researchers involved in this study. “Without gravity, there’s no sedimentation, the molecules can rotate and assemble freely, and make better structures.”

Scientists from The Johns Hopkins University, the Mayo Clinic, and Tufts University have developed a potential new way to treat a variety of rare genetic diseases marked by too low levels of specific cellular proteins. To boost those proteins, the scientists created a genetic "tail" that attaches to messenger RNA (mRNA) molecules that churn out the proteins. To deliver these genetic tails, also called “mRNA boosters,” the scientists encased them in nanoparticles covered in lipids. The nanoparticles are naturally absorbed by cells through their fatty outer membranes. After the scientists administered the mRNA boosters to laboratory mice, each group of mice had 1.5 to two times more of the proteins specific to the mRNA boosters than control mice that did not receive the boosters.

Researchers from the University of Rhode Island and Brown University have shown that carbon nanotubes could be combined with machine learning to detect subtle differences between closely related immune cells. The researchers used an in vitro experiment that involved placing live cells into a culture dish, adding carbon nanotubes, and then using a specialized microscope with an infrared camera to observe the emitted light from each cell. The camera generated millions of data points, each of which reflected cellular activity. Healthy cells emitted one type of light, while potentially unhealthy or changing cells emitted different light patterns.

Researchers from Carnegie Mellon University and the University of Southern California have devised a method to create large amounts of a material that can be used to make two-dimensional (2D) semiconductors with record high performance. That material, tellurium, has a fast conducting speed and is stable in the air, so it does not easily degrade. The researchers used 2D tellurium to create an ultralight-weight photodetector – a device that can detect light –  which is highly tunable, allowing its parameters to be changed so it can be used in a variety of applications, a property that is not true of other photodetectors. 

Researchers from Penn State, the University of North Texas, the University of Pennsylvania, Université Paris-Saclay in France, and the National Institute for Materials Science in Tsukuba, Japan, have shown that the light emitted from two-dimensional (2D) materials can be modulated by embedding a second 2D material, called a nanodot, inside them. The researchers showed that by controlling the nanodot size, they could change the color and frequency of the emitted light. The control came from adjusting the band gaps of the materials – essentially the energy threshold electrons must cross to make a material emit light.

Researchers from the Department of Energy’s (DOE) Lawrence Berkeley National Laboratory (Berkeley Lab); the University of California, Berkeley; and Northwestern University have developed a way to engineer pseudo-bonds in materials. Instead of forming chemical bonds – which is what makes epoxies and other composites tough – the chains of molecules entangle in a way that is fully reversible. The researchers attached polystyrene chains to 100-nanometers-diameter silica particles to create “hairy particles.” These hairy particles self-assembled into a crystal-like structure, and the space available to each polystyrene chain depended on its position in the structure. While some chains became rigid under confinement, others ultimately disentangled and stretched. The result was a strong, tough, thin-film material, held firmly together by pseudo bonds of tangled polystyrene chains. The research was conducted, in part, at the Molecular Foundry, a DOE Office of Science user facility at Berkeley Lab.

Researchers from the California NanoSystems Institute (CNSI) at the University of California, Los Angeles, have developed a patented technology that can inhibit and prevent the growth of pancreatic cancer in the liver. The technology’s goal is to reprogram the liver’s immune defense to attack pancreatic cancer. Key to this technology are liver-targeting nanoparticles that deliver two key components: an mRNA vaccine targeting an immune-activating marker commonly found in pancreatic cancer, and a small molecule that boosts the immune response. “This technology could potentially change the course of metastatic pancreatic cancer, as well as preventing spread to the liver in newly diagnosed patients without metastases,” said André Nel, one of the scientists involved in this study.

Researchers from the Singapore-Massachusetts Institute of Technology (MIT) Alliance for Research and Technology in Singapore, in collaboration with Temasek Life Sciences Laboratory (TLL) and MIT, have developed a groundbreaking near-infrared fluorescent nanosensor that can simultaneously detect and differentiate between iron (II) and iron (III) in living plants. This first-of-its-kind nanosensor allows precise localization of iron in plant tissues or subcellular compartments, enabling the measurement of even minute changes in iron levels within plants. The nanosensor features single-walled carbon nanotubes wrapped in a negatively charged fluorescent polymer, forming a structure that interacts differently with iron (II) and iron (III).

Scientists from the U.S. Department of Energy’s Berkeley National Laboratory; the University of California, Berkeley; and Adamas Nanotechnologies Inc. in Raleigh, NC, have encased nanodiamonds – diamonds that are less than 100 nanometers in size – in tiny moving droplets of water to improve quantum sensing, a technology that uses quantum mechanics to measure physical quantities with high precision. As the droplets flowed past a laser and were hit by microwaves, the nanodiamonds gave off light. The amount of light in the presence of a microwave field was related to the materials around the nanodiamond, letting scientists determine whether a chemical of interest was nearby.