(Funded by the National Institutes of Health and the National Science Foundation)
Researchers from Duke University, the University of California, Los Angeles, the Icahn School of Medicine at Mount Sinai, and Harvard Medical School have developed a platform that uses sound waves as acoustic tweezers to sort viruses from other compounds in a liquid. The platform consists of a rectangular chip with a sample-loading inlet at one end and separate virus and waste outlets at the other end. Two acoustic beams were applied across the chip, perpendicular to the sample flow. Particles larger than 150 nanometers (nm) in diameter were trapped on the chip, particles smaller than 50 nm left through the waste outlet, and viruses of intermediate sizes (50 to 150 nm) were collected via the virus outlet.

(Funded by the National Science Foundation, the National Institutes of Health, and the U.S. Department of Defense)
Researchers at Stanford University have developed a new way to see organs within a body by rendering overlying tissues transparent to visible light. The counterintuitive process – a topical application of a common food dye – was reversible in tests with animal subjects and may ultimately apply to a wide range of medical diagnostics, from locating injuries to monitoring digestive disorders to identifying cancers. To conduct their research, the scientists used a tool called an ellipsometer at the Stanford Nano Shared Facilities – open access facilities that are part of the National Science Foundation-funded National Nanotechnology Coordinated Infrastructure (NNCI). “Open access to such instrumentation is foundational for making groundbreaking discoveries, as those instruments can be deployed in new ways to generate fundamental insights about scientific phenomena,” said NSF Program Officer Richard Nash, who oversees the NSF NNCI.

(Funded by the National Science Foundation and the U.S. Department of Defense)
Researchers at the Massachusetts Institute of Technology have developed a new filtration material that might provide a nature-based solution to water contaminated by “forever chemicals,” or per- and poly-fluoroalkyl substances (PFAS). The filtration material, based on natural silk and cellulose, can remove a variety of these persistent chemicals, as well as heavy metals. The researchers devised a way of processing silk proteins into uniform nanoscale crystals, or “nanofibrils.” Then, they integrated cellulose into the silk-based fibrils, which formed a thin membrane that was highly effective at removing PFAS in lab tests.

(Funded by the National Institutes of Health and the National Science Foundation)
A research team from Brown University has developed a new method for transferring the ions that mass spectrometers analyze, dramatically reducing sample loss so that nearly all of it remains intact. “Basically, it’s a process where you’re really spraying your sample all over the place to produce these ions and only get a tiny portion of them into the mass spectrometer’s vacuum for analysis,” said Nicholas Drachman, a physics Ph.D. student who led the work. “Our approach skips all of that.” The key is a nanotube the researchers developed that has an opening about 30 nanometers across. For comparison, the conventional needle used in electrospray has an opening of about 20 micrometers across. The new nanotube also has the unique ability to transfer ions that are dissolved in water directly into the vacuum of a mass spectrometer, rather than producing a spray of droplets that must be dried out to access the ions.

(Funded by the National Science Foundation and the National Institutes of Health)
Researchers at the University of Pennsylvania have found that small extracellular vesicles are secreted by tumor cells and act as a “forcefield,” blocking nanoparticle-based therapies aimed at targeting cancers. “A lot like the Death Star with its surrounding fleet of fighter ships and protective shields, solid tumors can use features like immune cells and vasculature to exert force, acting as a physical barrier to rebel forces (nanoparticles) coming in to deliver the payload that destroys it,” said Michael Mitchell, one of the researchers involved in this study.