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

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. 

Chemists at Rice University working with researchers at the Ford Motor Company have turned plastic parts from "end-of-life" vehicles into graphene via the university's flash Joule heating process. To test whether end-of-life, mixed plastic could be transformed, the scientists ground the shredder "fluff" made of plastic bumpers, gaskets, carpets, mats, seating, and door casings from end-of-life F-150 pickup trucks to a fine powder. Powder heated between 10 to 16 seconds in low current produced a highly carbonized plastic, accounting for about 30% of the initial bulk. The other 70% was outgassed or recovered as hydrocarbon-rich waxes and oils.

Researchers from the University of Michigan and the University of Regensburg in Germany have created a laser pulse that sidesteps the inherent symmetry of light waves. This laser pulse, which emits terahertz light, could be used to manipulate quantum information, potentially bringing us closer to room-temperature quantum computing. The researchers created this laser pulse by carefully engineering nanosheets of a gallium arsenide semiconductor to design the terahertz emission through the motion of electrons and holes – the spaces left behind when electrons move in semiconductors.

Researchers at the University of Alabama at Birmingham have developed 100-nanometer hollow spheres, called polymersomes, that safely and efficiently carried genetic material to triple-negative breast cancer tumors in mice. There, the genetic material knocked down expression of a repair enzyme and gave breast cancer-bearing mice a fourfold increase in survival. 

Today, most mirrors used to direct a beam in high-power lasers are made by layering thin coatings of materials with different optical properties. But if there is even one, tiny defect in any of the layers, the powerful laser beam will burn through, causing the whole device to fail. Now, researchers at Harvard University have built a mirror out of a single material: diamond. By etching nanostructures onto the surface of a thin sheet of diamond, the research team built a highly reflective mirror that withstood, without damage, experiments with a 10-kilowatt laser.