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

Researchers from North Carolina State University have developed a patch that plants can "wear" to monitor continuously for plant diseases or other stresses, such as crop damage or extreme heat. Plants emit different combinations of volatile organic compounds under different circumstances. The rectangular patch is 30 millimeters long and consists of a flexible material containing graphene-based sensors and flexible silver nanowires. By targeting volatile organic compounds that are relevant to specific diseases or plant stress, the sensors can alert users to specific problems. 

Researchers from North Carolina State University have developed a patch that plants can "wear" to monitor continuously for plant diseases or other stresses, such as crop damage or extreme heat. Plants emit different combinations of volatile organic compounds under different circumstances. The rectangular patch is 30 millimeters long and consists of a flexible material containing graphene-based sensors and flexible silver nanowires. By targeting volatile organic compounds that are relevant to specific diseases or plant stress, the sensors can alert users to specific problems. 

A Rutgers-led team of researchers has developed a microchip that can measure stress hormones in real time from a drop of blood. Currently, measuring cortisol (a stress hormone) takes costly and cumbersome laboratory setups, so the Rutgers-led team looked for a way to monitor its natural fluctuations in daily life and provide patients with feedback that allows them to receive the right treatment at the right time. The researchers used the same technologies used to fabricate computer chips to build a nanowell array biosensor that can detect biomolecules at low levels. They validated the device's performance on 65 blood samples from patients with rheumatoid arthritis.

Researchers at the University of Colorado at Boulder have discovered that minuscule, self-propelled particles called nanoswimmers can escape from mazes as much as 20 times faster than other, passive particles, paving the way for their use in everything from industrial clean-ups to medication delivery. These nanoswimmers, also called Janus particles (named after a Roman two-headed god), are tiny spherical particles composed of polymer or silica, engineered with different chemical properties on each side of the sphere. One hemisphere promotes chemical reactions to occur, but not the other.

Engineers at the University of Pennsylvania have solved a major problem preventing metallic wood from being manufactured at meaningful sizes: eliminating the inverted cracks that form as the material is grown from millions of nanoscale particles to metal films big enough to build with. Preventing these defects allows strips of metallic wood to be assembled in areas 20,000 times greater than they were before. Metallic wood is a material that is very strong and light; it is full of regularly spaced nanoscale pores that significantly decrease its density without sacrificing its strength.

Researchers from Washington University in St. Louis and the University of Illinois at Chicago have developed a two-dimensional alloy material made from five metals as opposed to the traditional two. In a first for such a material, the researchers showed that it acted as an excellent catalyst for reducing carbon dioxide into carbon monoxide, with potential applications in environmental remediation.

A research team led by scientists at the U.S. Department of Energy's Lawrence Berkeley National Laboratory and the University of California, Berkeley, has developed a nanoparticle composite that grows into 3D crystals. The scientists say that the new material – which they call a 3D polymer-grafted nanoparticle crystal – could lead to new technologies that are 3D-grown rather than 3D-printed.

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.