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

Chemists at the Massachusetts Institute of Technology and the Dana-Farber Cancer Institute have designed a bottlebrush-shaped nanoparticle that can be loaded with multiple cancer drugs in ratios that can be easily controlled. In a study with mice, the researchers showed that nanoparticles carrying three drugs in the synergistic ratio they identified shrank tumors much more than when the three drugs were given at the same ratio but untethered to a nanoparticle. This nanoparticle platform could potentially be deployed to deliver drug combinations against a variety of cancers.

Researchers from the University of Rochester and HRL Laboratories LLC (Malibu, CA) have outlined a new method for controlling electron spin in silicon quantum dots – tiny, nanoscale semiconductors with remarkable properties. Electron spin – the magnetic moment associated with an electron – is a promising candidate for transferring, storing, and processing information in quantum computing. The standard method for controlling electron spin is electron spin resonance, which involves applying oscillating radiofrequency magnetic fields to the qubits, but this method has several limitations. The new method for controlling electron spin does not rely on oscillating electromagnetic fields but is based on a phenomenon called spin-valley coupling.

By repurposing one of the human body's natural cargo transports, researchers from Harvard University and the University of Nebraska-Lincoln have developed a vaccine platform that could curb certain challenges of vaccines. The researchers used extracellular vesicles – nanoparticles naturally present in cells – to which viral antigens were added to their surfaces. Then, the researchers tested the extracellular vesicles on mice. Those facing the flu virus without a vaccine survived less than 30% of the time, while those given three doses of the extracellular vesicle-based vaccine survived in 60–70% of cases.

Researchers from the University of Texas at Dallas; Lintec of America (Plano, TX); Wuhan University in China; and Hanyang University in South Korea have created a new type of a high-tech yarn called  a twistron, which generates electricity when stretched or twisted. Twistrons are constructed from carbon nanotubes that are twist-spun into high-strength, lightweight yarns. In the new study, the researchers intertwined three individual strands of spun carbon nanotube fibers to make a single yarn, similar to the way conventional yarns used in textiles are constructed.

When used as wearable medical devices, stretchy, flexible gas sensors can identify health conditions or issues by detecting oxygen or carbon dioxide levels in the breath or sweat, but manufacturing the devices, which are created using nanomaterials, can be a challenge. Now, Penn State University researchers have enhanced their gas sensor manufacturing process through an in situ laser-assisted manufacturing approach. In the process, a laser inscribes nanomaterials directly on top of a porous graphene foam substrate. The base material allows for the sensor to be stretchy and flexible when applied on the skin or an object.

Researchers at Drexel University have developed a thin film device, fabricated by spray coating, that can block electromagnetic radiation with the flip of a switch. The breakthrough, enabled by versatile two-dimensional materials called MXenes, could adjust the performance of electronic devices, strengthen wireless connections, and secure mobile communications against intrusion.

Researchers from the Massachusetts Institute of Technology; the University of Texas at Dallas; Washington University in St. Louis; the Institute for Basic Science in Pohang, South Korea; Sungkyunkwan University in Suwon-si, South Korea; Yonsei University in Seoul, South Korea; and ISAC Research Inc. in Daejeon, South Korea have developed a method that could enable chip manufacturers to fabricate ever-smaller transistors from 2D materials by growing them on existing wafers of silicon and other materials. With this method, the researchers fabricated a simple functional transistor from a type of 2D materials called transition-metal dichalcogenides, which are known to conduct electricity better than silicon at nanometer scales.

Researchers from the University of Pennsylvania, City University of New York, the University of Amsterdam in the Netherlands, and the AMOLF Institute’s Center for Nanophotonics in the Netherlands have created a nanostructured surface capable of solving equations using light. This discovery opens exciting new opportunities in the field of analog processing based on very thin nanostructured surfaces called metasurfaces. Optical analog processing refers to the use of light to perform analog computations, as opposed to traditional electronic methods which use electricity. 

There are many ways to initiate chemical reactions in liquids, but placing free electrons directly into liquid solutions is especially attractive for green chemistry because electrons in liquids, or solvated electrons, leave behind no side products after they react. Now, chemists at Rice University, Stanford University, and the University of Texas at Austin have uncovered the long-sought mechanism of a well-known but poorly understood process that produces solvated electrons via interactions between light and metal nanoparticles.

A collaborative team of researchers from Oregon Health and Science University and Oregon State University has developed an approach that uses lipid nanoparticles to deliver strands of messenger ribonucleic acid, or mRNA, inside the eye. The team demonstrated how the lipid nanoparticle delivery system targets light-sensitive cells in the eye, called photoreceptors, in both mice and nonhuman primates. The system’s nanoparticles are coated with a peptide that the researchers identified as being attracted to photoreceptors. “Improving the technologies used for gene therapy can provide more treatment options to prevent blindness,” says Renee Ryals, a scientist involved in this study. “Our study’s findings show that lipid nanoparticles could help us do just that.”