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

A team of scientists from Harvard University has created flexible, metal-free electrode arrays that snugly conform to the body’s myriad shapes, from the deep creases of the brain to the fibrous nerves of the heart. The electrode arrays, which can be stretched up to 10 times their length without breaking or tearing, consist of graphene flakes and carbon nanotubes embedded into alginate hydrogels. When living brain cells were grown on these electrode arrays, the cells displayed no damage, suggesting that the electrode arrays could be safely used on living tissues.

A research team at Harvard University has developed an approach in which specifically designed anti-inflammatory nanoparticles could be applied locally and selectively to chronically inflamed muscles that are severely affected or at more immediate risk of deterioration. In a mouse model of Duchenne muscular dystrophy – a genetic disorder characterized by progressive muscle degeneration and weakness – this strategy increased the volume of muscles covered by myofibers and improved muscle functions.

An international team led by researchers at Rice University and the University of Saskatchewan in Canada has developed a technique that may transform chemical catalysis by greatly increasing the number of transition-metal single atoms that can be placed into a carbon carrier. The technique uses graphene quantum dots, which are 3- to 5-nanometer particles of graphene, as anchoring supports. The quantum dots facilitate high-density transition-metal single atoms with enough space between the atoms to avoid clumping.

Engineers at the Institute for Soldier Nanotechnologies (a U.S. Army University-Affiliated Center at MIT), Caltech, and ETH Zürich have shown that nanoarchitected materials – which are designed from precisely patterned nanoscale structures – may be a promising route to lightweight armor, protective coatings, blast shields, and other impact-resistant materials. The researchers fabricated an ultralight material made from nanometer-scale carbon struts that give the material toughness and mechanical robustness. The team tested the material's resilience by shooting it with microparticles at supersonic speeds, and found that the material, which is thinner than the width of a human hair, prevented the miniature projectiles from tearing through it.

Engineers at Duke University have devised a system for manipulating particles approaching 2.5 nanometers in diameter by using sound-induced electric fields. The so-called "acoustoelectronic nanotweezers" provide a label-free, dynamically controllable method of moving and trapping nanoparticles over a large area. Precisely controlling nanoparticles is a crucial ability for many emerging technologies. For example, separating exosomes and other tiny biological molecules from blood could lead to new types of diagnostic tests for the early detection of tumors and neurodegenerative diseases.

By introducing nanoparticles into ordinary cement, researchers at Northwestern University have formed a smarter, more durable, and highly functional cement. The researchers used graphene nanoplatelets, a material rapidly gaining popularity in forming smart materials, to improve the resistance to fracture of ordinary cement. They showed that incorporating a small amount of the nanomaterial improved water transport properties, including pore structure and water penetration resistance, with reported relative decreases of 76% and 78%, respectively.

Engineers at Rice University have created microscopic seeds for growing remarkably uniform 2D perovskite crystals that are both stable and highly efficient at harvesting electricity from sunlight. In laboratory tests, photovoltaic devices made from the 2D perovskite crystals proved both efficient and reliable, a previously problematic combination for devices made from either 3D or 2D perovskites.

Scientists at Rice University have shown that adding organic fluorine compounds and fluoride precursors to elemental carbon black turns it into several hard-to-get allotropes when flashed, including fluorinated nanodiamonds, fluorinated turbostratic graphene, and fluorinated concentric carbon. The duration of the flash, between 10 and 500 milliseconds, determines the final carbon allotrope.

An international team of physicists led by the University of Minnesota has discovered that a unique superconducting metal is more resilient when used as a very thin layer only a few atomic layers thick. The research is the first step toward a larger goal of understanding unconventional superconducting states in materials, which could possibly be used in quantum computing in the future.

Nanoengineers at the University of California San Diego have developed immune cell-mimicking nanoparticles that target inflammation in the lungs and deliver drugs directly where they are needed. As a proof of concept, the researchers filled the nanoparticles with the drug dexamethasone and administered them to mice with inflamed lung tissue. Inflammation was completely treated in mice given the nanoparticles, at a drug concentration where standard delivery methods did not have any efficacy.