An official website of the United States government.
Pharmaceutical scientists at the University of Iowa have found that charged nanoparticles combined with a vaccine were effective in eliminating tumors or extending life span in mice with cancer. The nanoparticles, which were injected around melanoma tumors in mice, acted as a beacon of sorts, allowing melanoma-fighting immune cells triggered by the adenovirus vaccine to locate the tumor and overcome its defenses.
In order to optimize the properties of two-dimensional (2D) materials called MXenes, researchers need to be able to arrange 2D flakes of it into three-dimensional (3D) configurations. But there is a lack of reliable manufacturing methods available today for building MXenes into 3D configurations. Now, researchers at Carnegie Mellon University are developing a nanoscale additive manufacturing technology that will enable MXenes to be dispersed in liquid and deposited, layer by layer, into stacks of 3D structures to form electrochemical and physical sensors.
Rice University scientists who "flash" materials to synthesize graphene have turned their attention to boron nitride, which is highly valued for its thermal and chemical stability. The process exposes a precursor to rapid heating and cooling to produce two-dimensional materials, in this case pure boron nitride and boron carbon nitride. The technique can be tuned to prepare purified, microscopic flakes of boron nitride, with varying degrees of carbon. Experiments with the material showed that boron nitride flakes can be used as part of a powerful anti-corrosive coating.
Researchers from the University of Washington, Stanford University, the University of Maryland, MIT, and the Charles Stark Draper Laboratory in Cambridge, MA, have designed an energy-efficient, silicon-based non-volatile switch that manipulates light through the use of a phase-change material and a graphene heater. Previously, other researchers used doped silicon to heat the phase-change material, but this process is not very energy-efficient. So, in this study, the researchers used an un-doped silicon layer to propagate light and introduced a layer of graphene between the silicon and phase-change material to conduct electricity. This design eliminates wasted energy by directing all heat generated by the graphene to go toward changing the phase-change material.
In 2018, MIT researchers found that if two graphene layers are stacked at a specific “magic” angle, the twisted bilayer structure could exhibit robust superconductivity. Recently, the same group found that a similar superconductive state exists in twisted trilayer graphene — a structure made from three graphene layers stacked at a precise, new magic angle. This time, researchers from MIT and the National Institute for Materials Science in Tsukuba, Japan, have found that four and five graphene layers can be twisted and stacked at new angles to elicit robust superconductivity at low temperatures. This latest discovery establishes the various twisted and stacked configurations of graphene as the first known family of multilayer magic-angle superconductors.
Researchers from the University of Texas at Dallas and Yale University have demonstrated an atomically thin, intelligent quantum sensor that can simultaneously detect all the fundamental properties of an incoming light wave. The device exploits the unique physical properties of a novel family of two-dimensional materials, called moiré metamaterials, that have periodic structures and are atomically thin – in this case, two layers of twisted bilayer graphene, for a total of four atomic layers.
Engineers at the University of Illinois Urbana-Champaign have developed a method to visualize structures of small molecules clearly. The method is adapted from a technique, called cryogenic electron microscopy, which is used to capture high-quality images of the structures of larger molecules. But unlike large molecules, the imaging signals from small molecules are easily overwhelmed by their surroundings. So, the engineers used graphene – a single layer of carbon atoms that form a tight, hexagon-shaped honeycomb lattice – to temper the small molecules’ environment.
Researchers from The University of Texas at Austin and Xi’an Jiaotong University in China have created the first ever solid-state optical nanomotor. The nanomotor is less than 100 nanometers wide, and it can rotate on a solid substrate under light illumination and serve as a fuel-free and gear-free engine to convert light into mechanical energy. Nanomotors serve as a middle ground in scale between molecular machines at the smaller end and micro-engines at the larger end.
Researchers at Georgia State University have developed a new universal flu vaccine that offers broad defense against different strains of the influenza B virus. The double-layered protein nanoparticle vaccine, which is constructed with a stabilized portion of the influenza virus, induced broadly reactive immune responses and conferred robust and sustained cross-immune protection against the virus. The nanoparticle vaccine was tested in cell culture and in mice.
Researchers from Tufts University describe some of the latest advances in wearable electronic devices and systems that are being developed using electrospinning – the fabrication of nanofibers with tunable properties from a polymer base – and showcase advantages electrospun materials have over conventional bulk materials. For example, their high surface-to-volume ratio endows them with enhanced porosity and breathability. Also, conductive electrospun nanofibers provide high-surface-area electrodes, enabling flexibility, rapid charging, and high energy storage.
