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

Kevin Yager – leader of the electronic nanomaterials group at the Center for Functional Nanomaterials, a U.S. Department of Energy (DOE) Office of Science User Facility at DOE's Brookhaven National Laboratory – has imagined how recent advances in artificial intelligence and machine learning could help with scientific brainstorming and ideation. To accomplish this, he has developed a chatbot that is knowledgeable in areas of nanomaterial science that other bots are not.

According to Purdue University researchers, the thermal properties of graphene, a material which consists of a single layer of carbon atoms, may not be as revolutionary as previously thought. Thermal conductivity is measured in watts per meter per Kelvin. On this scale, a diamond's thermal conductivity is generally understood to be about 2,000. But when scientists started measuring graphene's thermal conductivity, early estimates reached above 5,000. But the Purdue University researchers have predicted the thermal conductivity of graphene at room temperature to be 1,300 – not only less than diamond but also less than the raw graphite material that graphene is made from.

Researchers from Washington University in St. Louis, the Massachusetts Institute of Technology, Yonsei University, Inha University, Georgia Institute of Technology, and the University of Notre Dame have demonstrated monolithic 3D integration of layered 2D materials into novel processing hardware for artificial intelligence computing. The device contains six atomically thin 2D layers, each with its own function, and achieves significantly reduced processing time, power consumption, latency, and footprint. This is accomplished through tightly packing the processing layers to ensure dense interlayer connectivity. This discovery offers a novel solution to integrate electronics and opens the door to a new era of multifunctional computing hardware.

Northwestern University synthetic biologists have developed a delivery system that binds to target cells and effectively transfers drugs inside. The workhorses behind this new system are extracellular vesicles – tiny, virus-sized nanoparticles that all cells already naturally produce. The researchers built DNA "programs" that, when inserted into "producer" cells, direct those cells to self-assemble extracellular vesicles and to produce and load them with biological drugs. In proof-of-concept experiments, the particles successfully delivered biological drugs to T cells, which are notoriously difficult to target. 

Ultrasmall fluorescent core-shell hybrid silica nanoparticles – known as Cornell Prime Dots – are among the nanocarriers for therapeutics that were thought to be viable only by injection, but new Cornell research has shown the potential for their oral administration. The researchers found that particles below 20 nanometers displayed high enough permeability through the mucosal layer and the epithelium for oral delivery. The group then performed oral delivery experiments in a small number of mice and found uptake in the bloodstream and successful renal clearance.

Researchers from Johns Hopkins University, Harvard University, and Korea University in Seoul have developed a tiny device that may hold promise for restoring mobility to those with lower limb paralysis. The novel apparatus, a spinal stimulator, can be placed below the injury site through a simple injection. The researchers first identified a new site for stimulation, the ventrolateral epidural surface, which is very close to crucial motor neurons in the spinal cord and accessible without surgery. Then, they designed a nanoscale, ultra-flexible, and stretchable device that can be inserted via a small injector and a simple syringe pump.

Researchers from Caltech have developed a new method for making a mode-locked laser on a photonic chip. The laser is made using nanoscale components, so it can be integrated into a light-based circuit similar to electricity-based integrated circuits found in modern electronics.

To know for sure whether a metamaterial will stand up to expectation, physically testing them is needed. But there is no reliable way to push and pull on metamaterials at the microscale without contacting and physically damaging them in the process. A technique, developed by engineers from the Massachusetts Institute of Technology (MIT) (including the MIT Institute for Soldier Nanotechnologies) and the Kansas City National Security Campus, probes metamaterials with a system of two lasers — one to quickly zap a structure and the other to measure the ways in which it vibrates in response, much like striking a bell with a mallet and recording its reverb. In contrast to a mallet, though, the lasers make no physical contact.

Researchers from the Massachusetts Institute of Technology and the U.S. Department of Energy’s Argonne National Laboratory and Brookhaven National Laboratory have demonstrated a way to precisely control the size, composition, and other properties of nanoparticles key to reactions involved in clean energy and environmental technologies. They did so by leveraging ion irradiation, a technique in which beams of charged particles bombard a material.

Researchers from the University of Pennsylvania have developed a lipid nanoparticle platform to deliver messenger RNA (mRNA) to T cells for applications in autoimmunity. “The major challenges associated with ex vivo (outside the body) cell engineering are efficiency, toxicity, and scale-up. Our mRNA lipid nanoparticles allow us to overcome all of these issues,” says Michael Mitchell, one of the scientists involved in this study. “Our work’s novelty comes from three major components: first, the use of mRNA, which allows for the generation of transient immunosuppressive cells; second, the use of [lipid nanoparticles], which allow for effective delivery of mRNA and efficient cell engineering; and last, the ex vivo engineering of primary human T cells for autoimmune diseases, offering the most direct pipeline for clinical translation of this therapy from bench to bedside.”