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

In the 1970s, scientists began exploring ways to extend electronic frequency mixing into the terahertz range using diodes. While these early efforts showed promise, progress stalled for decades. Recently, however, advances in nanotechnology have reignited this area of research. Now, researchers at the Massachusetts Institute of Technology have developed an electronic frequency mixer for signal detection that operates beyond 0.350 petahertz using tiny nanoantennae. These nanoantennae can mix different frequencies of light, enabling analysis of signals oscillating orders of magnitude faster than the fastest signal accessible to conventional electronics.

Researchers from the University of California, Riverside, and the University of Minnesota have developed magnetic nanoparticles that ensure safe rewarming of frozen tissues for transplant and address the issue of uneven heating due to inhomogeneous nanoparticle distribution. The researchers immersed animal tissues in a solution containing magnetic nanoparticles and a cryoprotective substance, and the solution was subsequently frozen with liquid nitrogen. The researchers then applied an alternating magnetic field, which initiated the rapid rewarming of the tissues, followed by a horizontal static magnetic field, which realigned the nanoparticles, effectively tapping the brakes on heat production.

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.

Researchers from the University of Massachusetts Amherst and the University of Massachusetts Chan Medical School have demonstrated in mice a new method to combat pancreatic cancer that relies on a nanoparticle drug-delivery system to activate an immune pathway, which usually recognizes viral infections in the body, in combination with tumor-targeting agents. "If we can trick the immune system into thinking that there is a viral-type infection, then we harness a very robust anti-tumor immune response to bring in for tumor immunotherapy," said Prabhani Atukorale, one of the scientists involved in this study.

Researchers from Caltech, the University of Washington, the University of Pennsylvania, the University at Albany, the Rockefeller University, the University of Edinburgh, Creative BioSolutions, LLC (Miami, FL), HDT Bio (Seattle, WA), Acuitas Therapeutics (Vancouver, Canada), and Ingenza Ltd. (RoslIn, United Kingdom) have developed and tested a new COVID-19 vaccine candidate called mosaic-8 that has shown potential to protect against different types of sarbecoviruses, including SARS-CoV-2 (the virus that causes COVID-19) and its variants. The mosaic-8 vaccine is made up of nanoparticles that elicit antibodies against conserved features of sarbecoviruses. Each nanoparticle contains pieces of eight different sarbecoviruses. These pieces are regions of the viruses' spike protein, called receptor-binding domains (RBDs), that are crucial for the virus to infect a cell. Mosaic-8 is now being prepared for initial human clinical trials.

Researchers at the University of Notre Dame have developed an automated device that can diagnose glioblastoma, an incurable brain cancer, in less than an hour. The device features a biochip that uses a sensor that detects biomarkers, called active Epidermal Growth Factor Receptors (EGFRs), that are overexpressed in glioblastoma. EGFRs are found on extracellular vesicles – structures that carry cargo between cells. The device also features silica nanoparticles that report the presence of active EGFRs on the captured extracellular vesicles, while bringing a high negative charge. 

This summer, middle school teachers from the Bay Area and Southern California have participated in NanoSIMST, a professional development program run by nano@stanford, one of the 16 sites of the National Science Foundation-funded National Nanotechnology Coordinated Infrastructure. The program is designed to connect the teachers with activities, skills, and knowledge about science at the scale of molecules and atoms, so they can incorporate it into their curriculum. NanoSIMST also prioritizes teachers from Title I schools, which are low-income schools with low-income student populations that receive federal funding to improve academic achievement. “There’s a gap in professional development for middle school teachers,” said Daniella Duran, the director of education and outreach for nano@stanford. “But these teachers are in a special place – they can teach their students early on about these amazing sciences and help them develop a picture of themselves as a scientist, engineer, or technician.” 

Researchers from Rice University, Vanderbilt University, and the U.S. Department of Energy’s Oak Ridge National Laboratory have developed a system for culturing cancer cell clusters that can shed light on hard-to-study tumor properties. The new zinc oxide-based culturing surface mimics the nanoscale roughness of the lotus leaf surface structure, providing a highly tunable platform for the high-throughput generation of three-dimensional nanoscale tumor models. The superhydrophobic array device can be used to create models for studying the progression of cancer, including metastasis – the stage in the disease when cancerous cells travel through the bloodstream from a primary tumor site to other parts of the body.

Researchers at the City University of New York have experimentally demonstrated that metasurfaces (two-dimensional materials structured at the nanoscale) can precisely control the optical properties of thermal radiation generated within the metasurface itself. This work paves the way for creating custom light sources with unprecedented capabilities. Metasurfaces offer a solution for greater utility by controlling electromagnetic waves through meticulously engineered shapes of nanopillars that are arrayed across their surfaces. 

Researchers from Harvard University and the University of Castilla-La Mancha in Spain have been able to successfully put tadpoles into a hibernation-like torpor state using donepezil, a drug approved by the U.S. Food and Drug Administration to treat Alzheimer's. This advance means that donepezil could potentially be repurposed for use in emergency situations to prevent irreversible organ injury while a person is being transported to a hospital. When used on its own, the drug seemed to cause some toxicity in the tadpoles, so the researchers encapsulated donepezil inside lipid nanocarriers, which reduced toxicity and caused the drug to accumulate in the tadpoles’ brain tissue – a promising result, because the central nervous system is known to mediate hibernation and torpor in animals.