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A pioneering method to simulate how nanoparticles move through the air could boost efforts to combat air pollution, suggests a study in the Journal of Computational Physics.

Tiny particles found in exhaust fumes, wildfire smoke and other forms of airborne pollution are linked with serious health conditions such as stroke, and cancer, but predicting how they move is notoriously difficult, researchers say.

Now, scientists have developed a new computer modeling approach that dramatically improves the accuracy and efficiency of simulating how nanoparticles behave in the air. In practice, this could mean simulations that can currently take weeks to run could be completed in a matter of hours, the team says.

From smartphones and TVs to credit cards, technologies that manipulate light are deeply embedded in our daily lives, many of which are based on holography. However, conventional holographic technologies have faced limitations, particularly in displaying multiple images on a single screen and in maintaining high-resolution image quality.

Recently, a research team led by Professor Junsuk Rho at POSTECH (Pohang University of Science and Technology) has developed a groundbreaking metasurface technology that can display up to 36 on a surface thinner than a . This research has been published in Advanced Science.

This achievement is driven by a special nanostructure known as a metasurface. Hundreds of times thinner than a human hair, the metasurface is capable of precisely manipulating light as it passes through. The team fabricated nanometer-scale pillars using silicon nitride, a material known for its robustness and excellent optical transparency. These pillars, referred to as meta-atoms, allow for fine control of light on the metasurface.

Putting hypersensitive quantum sensors in a living cell is a promising path for tracking cell growth and diagnosing diseases—even cancers—in their early stages.

Many of the best, most powerful quantum sensors can be created in small bits of diamond, but that leads to a separate issue: It’s hard to stick a diamond in a cell and get it to work.

“All kinds of those processes that you really need to probe on a , you cannot use something very big. You have to go inside the cell. For that, we need nanoparticles,” said University of Chicago Pritzker School of Molecular Engineering Ph.D. candidate Uri Zvi. “People have used diamond nanocrystals as biosensors before, but they discovered that they perform worse than what we would expect. Significantly worse.”

Wenzhou Medical University researchers have reimagined the spleen as a viable site for islet transplantation, enabling long-term diabetes control without the burden of full immunosuppression. Nanoparticle-driven spleen remodeling allowed transplanted mouse, rat, and human islets to restore normal blood sugar in diabetic rodents and cynomolgus macaques.

In type 1 diabetes, the immune system destroys native beta cells, the housed within pancreatic clusters called islets of Langerhans. Islet transplantation transfers these clusters from donor pancreases into the portal vein of the recipient’s liver, where they settle in the hepatic microvasculature. Once in place, they resume insulin secretion to reduce or eliminate injections and restore .

Liver-based transplantation has significant drawbacks. Immune attack, low oxygen tension, and the rigidity of hepatic tissue often destroy most transplanted islets within hours. Upward of 70% of cells are destroyed before engraftment, forcing reliance on multiple donors per recipient and blunting therapeutic success.

Exosomes have huge potential for drug delivery, but drug loading can be difficult. Here, the authors report on fusogenic lipid nanoparticles which, when mixed with exosomes rapidly fuse, non-destructively loading large drugs without compromising exosome biological functions, and demonstrate neurological application.

The COVID-19 pandemic increased public awareness of the importance of mask use for personal protection. However, when the mesh size of mask fabrics is small enough to capture viruses, which are usually around one hundred nanometers in size, the fabric typically also restricts air flow, resulting in user discomfort. Researchers from Japan have now developed a new filter material that effectively captures nanoparticles, although further improvements are needed to make it suitable for comfortable mask use.

In a study published this month in Materials Advances, researchers from the Institute of Industrial Science at the University of Tokyo have developed a filter capable of capturing nanoparticles such as viruses. While the filter demonstrates high filtration efficiency, its airflow resistance is currently higher than the standards required for face masks, indicating that additional development is necessary before it can be used for personal protective equipment.

The filter is constructed from nanosheets consisting of an ordered mesh composed of porphyrins, which are flat, ring-shaped molecules with a central hole. The in the porphyrin molecules are suitably sized to allow the easy passage of the small gas molecules in air while blocking the movement of larger particles, such as viruses. The nanosheets are then supported on a fabric modified with nanofibers containing pores of several hundred nanometers to form the filter.

Despite improvements to air filtration technology in the aftermath of the COVID-19 pandemic, some of the smallest particles—those of automobile and factory emissions—can still make their way through less efficient, but common filters. An interdisciplinary team of researchers from Drexel University’s College of Engineering have introduced a new way to improve textile-based filters by coating them with a type of two-dimensional nanomaterial called MXene.

Recently published in the journal C—Journal of Carbon Research, the team’s research reports that a non-woven polyester textile—a low-cost material with low filtration efficiency—coated with a thin layer of MXene nanomaterial can turn it into a potent filter capable of pulling some of the finest nanoparticles from the air.

“It can be challenging for common filters to contend with particles less than 100 nanometers, which include those emitted by industrial processes and automobiles,” said Michael Waring, Ph.D., a professor in Drexel’s College of Engineering, and co-author of the research. “Being able to augment a filter, through a simple coating process, to make it effective against these emissions is a significant development.”

Based on the principle of refractive index matching, highly transparent upconversion contact lenses (UCLs) with a high concentration of upconversion nanoparticles (UCNPs) were developed. These lenses efficiently convert multispectral near-infrared (NIR) light into the three primary visible colors, enabling humans to acquire wearable NIR color vision.

Scientists in China have developed contact lenses that let wearers see light normally invisible to the human eye. Cooler still, the lenses work better through closed eyelids, and other versions could help correct color blindness.

The human eye can see a relatively limited range of colors – light with wavelengths of between about 400 and 700 nanometers. In typical human-centric fashion, we call that the ‘visible’ part of the spectrum, even though other animals can see beyond it.

In a new study, scientists have helped humans catch a glimpse of light between 800 and 1,600 nanometers in length, a range we normally can’t see known as infrared. The trick is to pop in a pair of contact lenses embedded with nanoparticles that convert the infrared wavelengths into visible ones.

Neuroscientists and materials scientists have created contact lenses that enable infrared vision in both humans and mice by converting infrared light into visible light. Unlike infrared night vision goggles, the contact lenses, described in the journal Cell, do not require a power source—and they enable the wearer to perceive multiple infrared wavelengths. Because they’re transparent, users can see both infrared and visible light simultaneously, though infrared vision was enhanced when participants had their eyes closed.

“Our research opens up the potential for noninvasive wearable devices to give people super-vision,” says senior author Tian Xue, a neuroscientist at the University of Science and Technology of China. “There are many potential applications right away for this material. For example, flickering infrared light could be used to transmit information in security, rescue, encryption or anti-counterfeiting settings.”

The contact lens technology uses nanoparticles that absorb infrared light and convert it into wavelengths that are visible to mammalian eyes (e.g., in the 400–700 nm range). The nanoparticles specifically enable the detection of “near-infrared light,” which is infrared light in the 800‑1600 nm range, just beyond what humans can already see.