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

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. 

Copper plays a key role in the growth and development of cells. Because cancer cells grow and multiply more rapidly than non-cancer cells, they have a significantly higher need for copper ions. Restricting their access to copper ions could be a new therapeutic approach. The problem is that it has, so far, not been possible to develop a system that binds copper ions with sufficient affinity to "take them away" from copper-binding biomolecules. Now, researchers from Stanford University School of Medicine and the Max Planck Institute for Polymer Research in Mainz, Germany, have successfully developed such a system, which ensures that individual peptide molecules aggregate into nanofibers once they are inside the tumor cells. In this form, the nanofiber surfaces have many copper-binding sites in the right spatial orientation to be able to grasp copper ions. 

Researchers from the University of Illinois at Urbana-Champaign have discovered a new type of nanoparticle, palladium hydride, which contains palladium and hydrogen. Palladium hydride nanoparticles are typically structured symmetrically, looking like a cube with palladium atoms posted at each corner and centered on all six cubic faces. In contrast, the new nanoparticle’s structure is presumably the least symmetrical of all crystal systems. To create this unusual nanoparticle, the researchers added electrons to a solution containing palladium ions and water, and the electrons' negative charge pulled positive hydrogen ions from the water molecules, allowing the hydrogen ions to bond with the palladium ions. 

Scientists from Washington State University and the U.S. Department of Energy’s Lawrence Berkeley National Laboratory have discovered a way to make ions move more than ten times faster in mixed organic ion-electronic conductors. These conductors combine the advantages of the ion signaling used by many biological systems with the electron signaling used by computers. The new development speeds up ion movement in these conductors by using molecules that attract and concentrate ions into a separate nanochannel creating a type of tiny “ion superhighway.” These types of conductors hold a lot of potential because they allow movement of both ions and electrons at once, which is critical for battery charging and energy storage. 

Physicists at the Massachusetts Institute of Technology (MIT) have taken a key step toward solving the puzzle of what leads electrons to split into fractions of themselves. The new work is an effort to make sense of a discovery that was reported earlier this year by other physicists at MIT, who found that electrons appear to exhibit "fractional charge" in pentalayer graphene – a configuration of five graphene layers that are stacked atop a similarly structured sheet of boron nitride. Through calculations of quantum mechanical interactions, the scientists showed that the electrons form a sort of crystal structure, the properties of which are ideal for fractions of electrons to emerge. “This crystal has a whole set of unusual properties that are different from ordinary crystals, and leads to many fascinating questions for future research,” said Senthil Todadri, the scientist who led the new study.

Many messenger RNA (mRNA) medicines contain tiny fatty spheres, known as lipid nanoparticles, that encode proteins used by the body to treat or prevent a variety of illnesses. But most versions of lipid nanoparticles for the delivery of mRNA don't work for inhalable medications, because the nanoparticles clump together or increase in size when sprayed into the air. Now, researchers at the Massachusetts Institute of Technology have shown that a polymer with repeating units of positively and negatively charged components – called a zwitterionic polymer – can enable mRNA-containing lipid nanoparticles to withstand nebulization (turning a liquid into a mist).

Researchers from Case Western Reserve University, the University of Virginia, Cleveland Clinic, the University of Maryland School of Medicine, University Hospitals Cleveland Medical Center, the Louis Stokes Veterans Affairs Medical Center (Cleveland, OH), and CVPath Institute, Inc. (Gaithersburg, MD) have identified a new target to treat atherosclerosis, a condition where plaque clogs arteries and causes major cardiac issues, including stroke and heart attack. The researchers identified an inflammation-reducing molecule, called itaconate, and developed a new lipid nanoparticle-based treatment that allows itaconate to accumulate in plaque and bone marrow, where it reduces inflammation. "We've found that itaconate is crucial to the diet's ability to stabilize plaques and reduce inflammation, which has been a mystery until now," said Andrei Maiseyeu, one of the scientists involved in this study. "This discovery marks a major leap forward in the understanding of how diet-induced plaque resolution occurs at a molecular level." 

Researchers at the University of Massachusetts Amherst and the University of Massachusetts-Chan Medical School in Springfield, MA, have invented a new, sprayable delivery system for psoriasis medication that can be applied easily and locally to psoriasis lesions. The delivery system makes use of nanoparticles that contain psoriasis drugs, and these nanoparticles act like a trojan horse – the immune cells do not recognize the nanoparticles as a threat, but the medication they carry disrupts the overactive immune response. The researchers designed and tested nanoparticles in different shapes: rods, ellipses and spheres and discovered that nanorods inhibited 3.8 times more inflammation due to psoriasis than nanoellipses and 4.5 times more than nanospheres.