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

Most of the tests that doctors use to diagnose cancer are based on imaging. Cancer can also be found with molecular diagnostics, which can detect specific cancer-associated molecules that circulate in bodily fluids, such as blood and urine. Now, engineers at MIT have created a new diagnostic nanoparticle that combines both of these features: It can reveal the presence of cancerous proteins through a urine test, and it functions as an imaging agent, pinpointing the tumor location.

Current biological treatments for autoimmune diseases consist of monoclonal antibodies that search out and destroy factors in the immune system, such as the tumor necrosis factor, that mistakenly mount immune attacks against the body. But these treatments often have side effects and can have varying degrees of effectiveness in different individuals. Now, engineers at Duke University have built nanostructures which chemically tether protein subunits that can stimulate the type of biological response necessary to sequester the disease-causing excess of tumor necrosis factor.

Using a pioneering imaging technique, researchers at Cornell University have obtained a high-resolution snapshot of how ligands – molecules that bind to other molecules or metals – interact with the surface of nanoparticles. In doing so, the researchers made an unexpected discovery: They determined that by varying the concentration of an individual ligand, they could control the shape of the particle to which it is attached. This approach could result in chemical sensors that are sensitive at a very low level to a specific chemical in the environment.

One of the main drivers of antimicrobial resistance is the misuse and overuse of antimicrobial agents, which includes silver nanoparticles, an advanced material with well-documented antimicrobial properties. Now, researchers at the University of Pittsburgh have used laboratory strains of E. coli to better understand bacterial resistance to silver nanoparticles. The researchers sequenced the genome of the E. coli that had been exposed to silver nanoparticles and found a mutation in a gene that corresponds to an efflux pump that pushes heavy metal ions out of the cell.

Optical singularities typically occur when the phase of light with a specific wavelength is undefined. These regions appear completely dark. Today, some optical singularities, including optical vortices, are being explored for use in optical communications and particle manipulation, but scientists are just beginning to understand the potential of these systems. Now, researchers from Harvard University have developed a new technique to control and shape optical singularities. To demonstrate their technique, the researchers created a singularity sheet in the shape of a heart by using flat metasurfaces with precisely shaped nanopillars to shape the singularities.

A “boiling crisis” is the rapid formation of a vapor film between the heating source and the liquid when the heat supply exceeds a critical value. New research by engineers at MIT offers insight into the phenomenon by using high-speed infrared cameras and machine learning. The goal was to estimate how close the water was to a boiling crisis. To collect data, the engineers boiled water on a surface of indium tin oxide, by itself or with one of three coatings: copper oxide nanoleaves, zinc oxide nanowires, or layers of silicon dioxide nanoparticles. The team found that 17 factors contributed significantly to prediction accuracy.

Researchers at the University of Michigan have developed a new chemical catalyst that could enable the production of more propylene, the feedstock for polypropylene, the world's second most widely used plastic. The new catalyst, which can make propylene from natural gas, is at least 10 times more efficient than current commercial catalysts and lasts 10 times longer before needing regeneration. It is made of platinum and tin nanoparticles supported by a framework of silica.

Scientists at the U.S. Department of Energy's Oak Ridge National Laboratory and the University of Tennessee, Knoxville, have found a way to simultaneously increase the strength and ductility of an alloy by introducing nanoprecipitates into its matrix and tuning their size and spacing. The nanoprecipitates are nanometer-sized solids that separate from the metal mixture as the alloy cools. The researchers carefully kept the composition of the matrix and the total amount of nanoprecipitates the same in different samples. However, they varied nanoprecipitate sizes and spacings by adjusting the processing temperature and time. As a result, the strength of the alloy increased by 20%–90% and its elongation increased by 300%.

Researchers at Kansas State University have demonstrated potential ways to manufacture graphene-based nano-inks for additive manufacturing of supercapacitors in the form of flexible and printable electronics. The researchers have also developed additive manufacturing of small supercapacitors – called micro-supercapacitors – so that one day, they could be used for wafer-scale integration in silicon processing.

Bioengineers and medical researchers at the University of Pennsylvania have designed a proof-of-concept microfluidic device containing 128 mixing channels working in parallel. The channels mix a precise amount of lipid and mRNA, crafting individual lipid nanoparticles on a miniaturized assembly line. The researchers tested the lipid nanoparticles produced by their device in a mouse study, showing that they could deliver therapeutic mRNA sequences with four-to-five times greater activity than those made by conventional methods.