(Funded by the U.S. Department of Energy, the U.S. Department of Defense, and the U.S. National Science Foundation)
Scientists from Oregon State University; the Molecular Foundry at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory; Columbia University; and the Autonomous University of Madrid, Spain, have discovered luminescent nanocrystals that can be quickly toggled from light to dark and back again. “Normally, luminescent materials give off light when they are excited by a laser and remain dark when they are not,” said Artiom Skripka, one of the scientists involved in this study. “In contrast, we were surprised to find that our nanocrystals live parallel lives. Under certain conditions, they show a peculiar behavior: They can be either bright or dark under exactly the same laser excitation wavelength and power.”

(Funded by the U.S. Department of Defense, the U.S. Department of Energy, the U.S. National Science Foundation, and the U.S. Department of State)
Researchers from Columbia University; the Molecular Foundry at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory; and the University of Utah have invented new nanoscale sensors of force. They are luminescent nanocrystals that can change intensity and/or color when you push or pull on them. These “all-optical” nanosensors are probed with light only and therefore allow for fully remote read-outs—no wires or connections are needed. The nanosensors have an operational range that spans more than four orders of magnitude in force – a much larger range than any previous optical nanosensor.

(Funded by the U.S. National Science Foundation and the U.S. Department of Defense)
Bright, twisted light can be produced with technology similar to an Edison light bulb, researchers at the University of Michigan have shown. Usually photons from a blackbody source (which is in thermodynamic equilibrium with its environment) are randomly polarized – their waves may oscillate along any axis. The new study revealed that if the emitter was twisted at the micro or nanoscale, with the length of each twist similar to the wavelength of the emitted light, the blackbody radiation would be twisted, too. This discovery adds nuance to fundamental physics while offering a new avenue for robotic vision systems and other applications for light that traces out a helix in space.

(Funded by the National Institutes of Health and the U.S. National Science Foundation)
Researchers from Georgia Tech, Emory University, and the University of California, Davis, have created a technique that could lead to new, less-invasive treatments for blood disorders and genetic diseases. “This would be an alternative to invasive hematopoietic stem cell therapies – we could just give you an IV drip,” said James Dahlman, one of the researchers involved in this study. “It simplifies the process and reduces the risks to patients.” The procedure uses lipid nanoparticles that carry genetic instructions to hematopoietic stem cells, but unlike current therapies, in this procedure, the nanoparticles don’t have targeting ligands, and they can dodge the liver, which acts as the body’s primary blood filter.

(Funded by the National Institutes of Health and the U.S. National Science Foundation)
Engineers at the University of Pennsylvania have modified lipid nanoparticles to not only cross the blood-brain barrier but also to target specific types of cells, including neurons. The researchers showed how short strings of amino acids can serve as precise targeting molecules, enabling the lipid nanoparticles to deliver mRNA specifically to the endothelial cells that line the blood vessels of the brain, as well as neurons. This breakthrough marks a significant step toward potential next-generation treatments for neurological diseases like Alzheimer’s and Parkinson’s.