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

A team of researchers at MIT, the University of California, Irvine, and other institutions has found a way to map phonons – vibrations in crystal lattices – in atomic resolution, enabling deeper understanding of the way heat travels through quantum dots, which are engineered nanostructures in electronic components. In particular, the researchers probed the dynamic behavior of phonons near a single quantum dot of silicon-germanium by using vibrational electron energy loss spectroscopy in a transmission electron microscope.

Several years ago, researchers showed that a promising therapeutic – using a protein, called stem cell factor, that can stimulate the growth of stem cells – could treat a variety of ailments, such as ischemia, heart attack, stroke, and radiation exposure. But during clinical trials, numerous patients suffered severe allergic reactions, and development of this therapeutic stopped. Now, a research team led by engineers at The University of Texas at Austin has developed a related therapeutic that they say avoids these major allergic reactions while maintaining its therapeutic activity. The key to the discovery was the use of a similar, membrane-bound version of the stem cell factor delivered in engineered lipid nanocarriers.

Researchers at Rice University have suggested, through computational models, that growing or stamping single-layer 2D materials on a carefully designed undulating surface would achieve "an unprecedented level of control" over their magnetic and electronic properties. The researchers say the discovery opens a path to explore interactions between multiple microscopic particles, including quantum systems. The researchers were inspired by recent discoveries that twisting or otherwise deforming 2D materials bilayers, such as bilayer graphene, induced interesting electronic and magnetic phenomena

Researchers at the University of Maine have developed containers out of recyclable wood composites with a new coating made of lignin-containing cellulose nanofibrils, which improves the quality of the containers for takeout purposes. The containers were also found to be fully recyclable. The researchers were able to disintegrate the samples and reform them, and the composites would retain their structure and oil- and grease-resistant properties. 

Scientists at Penn State have developed fiber actuators that mimic the structure of muscle fibers and could lead to advances in robotics, prosthetics, and smart clothing. The fibers consist of highly aligned nanoscale structures, with alternating crystalline and amorphous domains, that can stretch several times their original length when hydrated and can harden and lock in the elongated shape when dried in the extended state (but adding water or heat allows the material to snap back to its original size).

A team of MIT researchers has developed drug-carrying nanoparticles that appear to get into the brain more efficiently than drugs given on their own. Using a human tissue model they designed, which accurately replicates the blood-brain barrier – a barrier between the brain’s blood vessels and brain tissue – the researchers showed that the particles could get into tumors and kill glioblastoma cells. Glioblastoma is an aggressive type of cancer that can occur in the brain or spinal cord.

A team of researchers from Washington State University and the U.S. Department of Energy's Pacific Northwest National Laboratory has shown that a new artificial enzyme can chew through lignin, the tough polymer that helps woody plants hold their shape. Lignin, which is the second most abundant renewable carbon source on Earth, mostly goes to waste as a fuel source. The researchers replaced the peptides that surround the active site of natural enzymes with protein-like molecules called peptoids, which then self-assembled into nanoscale crystalline tubes and sheets. These artificial enzymes are more stable and robust than the natural versions, so they can work at temperatures up to 60 degrees Celsius, a temperature that would destroy a natural enzyme.

Researchers at The University of Texas M. D. Anderson Cancer Center have developed an ultrasound-guided cancer immunotherapy platform that generates systemic antitumor immunity and improves the therapeutic efficacy of immune checkpoint inhibitors. This approach uses nanocomplexes combined with microbubbles to effectively deliver a chemical compound involved in anticancer immunity into immune cells. In a preclinical study, the strategy demonstrated a complete tumor eradication rate of 60% when administered as monotherapy in breast cancer models.

Scientists at the University of Michigan were optimistic when they identified a small molecule that blocked a key pathway in brain tumors. But there was a problem: How to get the inhibitor through the bloodstream and into the brain to reach the tumor. In collaboration with multiple labs, the teams developed a nanoparticle to contain the inhibitor, and not only did the nanoparticles deliver the inhibitor to a tumor in mouse models, but the process also triggered immune memory, so that a reintroduced tumor was also eliminated.

Scientists at the U.S. Department of Energy’s Ames Laboratory have shown that if they change the sizes of catalytic nanoparticles that they had previously developed, the rate at which polymer chains are broken down is different depending on the size of the nanoparticles. The larger nanoparticles reacted with long polymer chains more slowly, while smaller polymer chains reacted more quickly.