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

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.

Researchers from Cornell University and the Army Research Laboratory have devised a new method for designing metals and alloys that can withstand extreme impacts. When a metallic material is struck at an extremely high speed, it immediately ruptures and fails. The reason for that failure is embrittlement – the material loses its ability to bend without breaking – when deformed rapidly. The researchers created a nanocrystalline alloy made of copper and tantalum in which dislocations could barely move more than a few nanometers before they were stopped in their tracks, effectively suppressing embrittlement. Dislocations are tiny defects that move through a crystal. During rapid, extreme strains, the dislocations accelerate and interact with lattice vibrations, which create substantial resistance that leads to embrittlement. 

Researchers from the U.S. Department of Energy’s (DOE) Oak Ridge National Laboratory (ORNL), Purdue University, and the University of Illinois Urbana−Champaign have used a nanoscale quantum sensor to measure spin fluctuations near a phase transition in a magnetic thin film. Thin films with magnetic properties at room temperature are essential for data storage, sensors and electronic devices because their magnetic properties can be precisely controlled and manipulated. The researchers used a specialized instrument called a scanning nitrogen-vacancy center microscope at the Center for Nanophase Materials Sciences, a DOE Office of Science user facility at ORNL. A nitrogen-vacancy center is an atomic-scale defect in diamond in which a nitrogen atom takes the place of a carbon atom, and a neighboring carbon atom is missing, creating a special configuration of quantum spin states.

Scientists have blended electron microscopy with artificial intelligence (AI) so they can observe the movements of atoms in nanoparticles at an unprecedented time resolution. Because the atoms are usually barely visible in electron microscope images, scientists cannot be sure how they are behaving. So, the scientists in this study trained a deep neural network, AI’s computational engine, that can “light up” the electron-microscope images, revealing the underlying atoms and their dynamic behaviors. “We have developed an artificial-intelligence method that opens a new window for the exploration of atomic-level structural dynamics in materials,” says Carlos Fernandez-Granda, one of the scientists involved in this study.

Researchers at Northwestern University have created a new platform for monitoring chemical contaminants in the environment. The platform can detect the metals lead and cadmium at concentrations down to two and one parts per billion, respectively, in a matter of minutes. It was created by interfacing nanomechanical microcantilevers with synthetic biology biosensors. When the tiny cantilevers are coated with DNA molecules, biosensing molecules bind to the DNA, causing the cantilevers to bend. When exposed to toxic metals, the biosensors unbind, causing the cantilever to “de-bend,” which can be measured precisely to detect the toxic metals.

Researchers from the University of Illinois Urbana-Champaign have developed organic-material-based nanozymes – synthetic nanomaterials that have enzyme-like catalytic properties – that are non-toxic, environmentally friendly, and cost effective. To create these nanozymes, the researchers used a novel particle synthesis technique that brought each nanozyme’s size down to less than 100 nanometers. In one study, the researchers showed that these nanozymes, combined with a colorimetric sensing platform, could detect the presence of histamine in spinach and eggplant. In another study, the nanozymes were used to detect the presence of glyphosate, a common agricultural herbicide, in plants. “We were able to show that our system doesn’t just work in the lab, it has the potential to be utilized for real-world applications as a cost-effective molecule sensing system for food and agriculture,” said Dong Hoon Lee, lead author of the study.

Researchers at the Massachusetts Institute of Technology (MIT), Brown University, and the Rhode Island School of Design in Providence, RI, have developed an autonomous programmable computer in the form of an elastic fiber, which could monitor health conditions and physical activity, alerting the wearer to potential health risks in real time. Clothing containing the fiber computer was comfortable and machine washable, and the fibers were nearly imperceptible to the wearer, the researchers report. “Our bodies broadcast gigabytes of data through the skin every second in the form of heat, sound, biochemicals, electrical potentials, and light, all of which carry information about our activities, emotions, and health. Wouldn’t it be great if we could teach clothes to capture, analyze, store, and communicate this important information in the form of valuable health and activity insights?” says Yoel Fink, senior author of a paper on the research and principal investigator in MIT’s Research Laboratory of Electronics and the Institute for Soldier Nanotechnologies at MIT.