Gestational Exposure to Flame Retardant Alters Brain Development in Rats

A new study from North Carolina State University shows that exposure in utero to the flame retardant FireMaster® 550 (FM 550), or to its individual brominated (BFR) or organophosphate ester (OPFR) components, resulted in altered brain development in newborn rats. The effects – most notably evidence of mitochondrial disruption and dysregulated choline and triglyceride levels in brain tissue – were greater in male offspring than in females. The work adds to the body of evidence that both OPFRs and BFRs can be neurotoxic.

FM 550 is a flame-retardant mixture first identified a decade ago. It was developed to replace PBDEs, a class of fire retardants being phased out due to safety concerns.

“While some new flame-retardant mixtures still contain BFRs, the OPFRs are a popular substitute for PBDEs, since it is believed that OPFRs don’t accumulate in the body and thus cannot be as harmful,” says Heather Patisaul, associate dean for research in NC State’s College of Sciences and corresponding author of the study. “Specifically, it was thought that OPFRs wouldn’t impact acetylcholinesterase – a key neurotransmitter. But it looks as though OPFRs still impact choline signaling and are just as bad if not worse than PBDEs for the developing brain.”

Patisaul and her colleagues performed transcriptomic and lipidomic studies on the prefrontal cortexes of newborn rats whose mothers had been exposed to FM550, or to BFR or OPFR elements individually, during gestation.

Scientists Created a Material Promising for Improving Brightness of Screens

One of the assembled organic LEDs based on push-pull systems.
Photo credit: Ruslan Gadirov / TSU

Scientists at the Postovsky Institute of Organic Synthesis, Ural Branch of the Russian Academy of Sciences, and Ural Federal University have developed, synthesized, and studied a series of new fluorophores - push-pull systems (compounds with pronounced electron-donor and electron-acceptor parts) based on cyanopyrazine. Ural chemists in cooperation with colleagues from Tomsk State University showed that the presence of a cyano group in the substance significantly increases the efficiency of organic light emitting diodes (OLEDs) based on it. This opens the prospect of creating new materials to enhance the brightness of displays of smartphones, computers and televisions. An article describing the research and its results was published in the journal Dyes and Pigments.

In previous research work, chemists demonstrated that one of the most promising compounds as an acceptor (attracting electrons) part in push-pull systems is the pyrazine ring (another name is 1,4-diazine), a compound of nitrogen, hydrogen and carbon that has a significant electron-accepting effect.

A revolutionary method to observe cell transport

Nanobodies (grey) with magnetic probes (red stars) target the desired membrane protein.
Credit: Bordignon, Enrica

Membrane proteins are key targets for many drugs. They are located between the outside and inside of our cells. Some of them, called ‘‘transporters’’, move certain substances in and out of the cellular environment. Yet, extracting and storing them for observation is particularly complex. A team from the University of Geneva (UNIGE), in collaboration with the University of Zurich (UZH), has developed an innovative method to study their structure in their native environment: the cell. The technique is based on electron spin resonance spectroscopy. These results, just published in the journal Science Advances, may facilitate future development of new drugs.

In living organisms, each cell is surrounded by a cell membrane (or ‘‘cytoplasmic membrane’’). This membrane consists of a double layer of lipids. It separates the contents of the cell from its direct environment and regulates the substances that can enter or leave the cell. The proteins attached to this membrane are called ‘‘membrane proteins’’.

Located at the interface between the outside and inside of the cell, they carry various substances across the membrane - into or out of the cell - and play a crucial role in cell signaling, i.e. in the communication system of cells that allows them to coordinate their metabolic processes, development and organization. As a result, membrane proteins represent more than 60% of current drug targets.

Ural Scientists Created Nanoparticle Growth Technology

The new material is suitable for solar cells, biosensors, and other systems working on quantum principles.
Photo credit: Vladimir Petrov

Physicists at Ural Federal University and their colleagues from the Institute of Electrophysics, Ural Branch of the Russian Academy of Sciences, and the Institute of Ion Plasma and Laser Technologies, Academy of Sciences, have developed a technology for growing nonspherical nanoparticles that are synthesized by ion implantation. With the new technique, it is possible to grow nanoparticles of different shapes and thus obtain the necessary properties and control them. The technology is applicable to different metals, both noble metals such as gold, silver, platinum, and "ordinary", the scientists assure. A description of the technology and the results of the first experiments - copper implantation in ceramics - are presented in the Journal of Physics and Chemistry of Solids.

"By changing the shape of nanoparticles from spherical to non-spherical, we were able to increase the range of optical absorption. This, in turn, is the basis for further converting the absorbed energy into electricity and heat. As a result, we can get more functional sensors and increase their sensitivity range. If such nanoparticles are built into lasers, their power will increase. If we talk about sensors, their sensitivity will increase. As for sensors, their response time will change. This is all due to the peculiarity of plasmon resonance, which leads to the fact that around the nanoparticles there is an amplified electric field," explains study co-author Arseny Kiryakov, Associate Professor at the Department of Physical Techniques and Devices for Quality Control at UrFU.

New Chemosensors Can Detect Heavy Metals in the Body and Environment

According to Grigory Zyryanov, industrial partners, including foreign ones, are interested in the developments.
Photo credit: Anna Marinovich

Ural scientists are developing chemosensors for the diagnosis and therapy of various diseases. These are compounds that change their luminescent properties upon external exposure or contact with organic cells. They can be used to find and suppress cancer cells, diagnose cardiovascular diseases, and determine the level of sugar or drugs in the blood. One of the new developments of scientists from the UrFU is chemosensors for controlling the content of metals in the blood, since an overdose of metals can be dangerous for the body. Grigory Zyryanov, professor at the Department of Organic and Biomolecular Chemistry at Ural Federal University, spoke about this on the air of Komsomolskaya Pravda radio.

"One of our activities is the creation of chemosensors for the detection of zinc cations in biological fluids, including blood. Zinc is involved in many physiological processes in the body; it is necessary for normal growth and stabilization of cell membranes. In some cases, such as colds, taking zinc supplements can help boost the body's immune response and speed recovery. However, it is necessary to control zinc levels, since zinc overdose is toxic for the body," explains Grigory Zyryanov.

Converting Carbon Dioxide to Minerals Underground

Mineralizing carbon dioxide underground is a potential carbon storage method.
Credit: Illustration by Cortland Johnson | Pacific Northwest National Laboratory

A new high-profile scientific review article in Nature Reviews Chemistry discusses how carbon dioxide (CO2) converts from a gas to a solid in ultrathin films of water on underground rock surfaces. These solid minerals, known as carbonates, are both stable and common.

“As global temperatures increase, so does the urgency to find ways to store carbon,” said Pacific Northwest National Laboratory (PNNL) Lab Fellow and coauthor Kevin Rosso. “By taking a critical look at our current understanding of carbon mineralization processes, we can find the essential-to-solve gaps for the next decade of work.”

Mineralization underground represents one way to keep CO2 locked away, unable to escape back into the air. But researchers first need to know how it happens before they can predict and control carbonate formation in realistic systems.

“Mitigating human emissions requires fundamental understanding how to store carbon,” said PNNL chemist Quin Miller, co-lead author of the scientific review featured on the journal cover. “There is a pressing need to integrate simulations, theory, and experiments to explore mineral carbonation problems.”

Developing Self-Complementary Macrocycles with Ingenious Molecules

Virus capsids can be formed through the self-complementary assembly of a single class of protein molecules. However, mimicking nature by making higher-ordered structures from artificial molecules has proven difficult to achieve. A new assembly method developed by Tokyo Tech researchers can produce stable and controllable supramolecular structures, from hexamers to cuboctahedrons that include 6 and 108 monomer units, respectively, opening doors to metal-free supramolecular assemblies.

Some biological molecules with efficient noncovalent bonding sites can use their bonding properties to create well-defined assemblies from a single class of molecules–i.e., they assemble with each other. These molecules, which are frequently seen in nature, are referred to as "self-complementary assemblies." For instance, the p24 protein hexamer, which is part of the capsid of the HIV (human immunodeficiency virus), is composed of six protein subunits which complementarily self -assemble using many hydrogen bonds. This phenomenon provides well-designed molecules can form higher-ordered assemblies without the metal ions which are commonly used as "joints" between monomer molecules. Indeed, many self-complementary assemblies have been reported on the basis of intrinsic hydrogen bonds, π-interactions, and coordination bonds.

Ural Scientists Developed a Drug to Combat Post-Covidal Complications

According to the scientists, the university and the Ural Branch of the Russian Academy of Sciences are developing world-class materials.
Photo credit: TASS-Ural Press Center, Vladislav Burnashev

Scientists from the Ural Federal University and the Postovsky Institute of Organic Synthesis have developed a drug to combat post-covidal complications, namely, the formation of blood clots. The drug blocks the release of clot-forming compounds caused by coronavirus infection. As the scientists point out, this is a world-class achievement, as new classes of compounds capable of combating the effects of coronavirus have been discovered. Representatives of the Ural Branch of the Russian Academy of Sciences talked about this, as well as about other developments aimed at ensuring the scientific and technological sovereignty of Russia, at a press conference at TASS.

"We develop unique things. This is important to note, because now the concept of import substitution is pushed to the background, and we are talking about the scientific and technological sovereignty of the country. The fact is that import substitution implies reproduction, copying of foreign technologies. We are catching up beforehand. Scientific and technological sovereignty implies independence from external conditions and supremacy in the development of industrial samples and new materials which are superior to foreign analogues in their characteristics. Therefore, it is certain that the Ural scientists successfully solve the task of ensuring scientific and technological progress," emphasizes Victor Rudenko, Academician and Chairman of the Ural Branch of the Russian Academy of Sciences.

Sustainable kerosene: accelerate production on an industrial scale

In the international project CARE-O-SENE, researchers are developing tailor-made Fischer-Tropsch catalysts for the production of sustainable kerosene.
Photo credit: Tiziana Carambia

The Federal Ministry of Education and Research (BMBF) is funding the international research project CARE-O-SENE (Catalyst Research for Sustainable Kerosene) with 30 million euros. It is intended to improve the production of sustainable kerosene on an industrial scale. For this purpose, the network partners, including the Karlsruhe Institute of Technology (KIT), are developing tailor-made catalysts to further develop the Fischer-Tropsch synthesis (FTS) established in fuel production for the use of renewable energy sources.

With a share of more than 80 percent, fossil fuels are still by far the most important raw material for fuels, heating and the chemical industry (source: International Energy Agency, IEA). Sustainable fuels are based on green hydrogen and carbon dioxide - and should make a significant contribution to decarbonizing sectors such as aviation, in which fossil fuels are particularly difficult to replace. In the CARE-O-SENE project, seven South African and German project partners are therefore researching next-generation Fischer-Tropsch catalysts.

Scientists Improve Inexpensive Perovskite Photocells

Simulated atomic structure of perovskite after calcium doping.
Illustration: Danil Bukhvalov

UrFU scientists have found a way to protect perovskite solar cells based on lead-methylammonium iodide (a promising alternative to traditional silicon photovoltaic cells) from degradation by water, such as rain. They found that partial replacement of lead with other alkaline earth metals protects them from such degradation, and also increases the parts of the visible spectrum of radiation involved in the process of generating electrons. An article on the results of the study was published in the Journal of Solid State Chemistry. The research was financially supported by the Ministry of Education and Science of Russia under the Priority 2030 development program of Ural Federal University.

Perovskite solar cells based on lead-methylammonium iodide are superior to silicon cells in performance and ease of synthesis. They are also capable of effectively generating electricity in cloudy or foggy conditions, so they are ideal for use in Russia or countries with similar climates. However, a complete switch to perovskite solar panels is not possible due to a number of reasons causing instability of such photovoltaic cells.

One of the causes of instability is that the compound is unstable to contact with water or other organic solvents. If it rains on the photocell, the compound begins to degrade rapidly, destroying its structure. Scientists determined that replacing lead with metals such as calcium, barium, or strontium would protect the compound from rapid degradation.

Engineering Duckweed to Produce Oil for Biofuels, Bioproducts

Brookhaven biochemists engineered duckweed, an aquatic plant, to produce large quantities of oil. If scaled up the approach could produce sustainable bio-based fuel without competing for high-value croplands while also potentially cleaning up agricultural wastewater.
Credit: Brookhaven National Laboratory

Scientists at the U.S. Department of Energy’s Brookhaven National Laboratory and collaborators at Cold Spring Harbor Laboratory (CSHL) have engineered duckweed to produce high yields of oil. The team added genes to one of nature’s fastest growing aquatic plants to “push” the synthesis of fatty acids, “pull” those fatty acids into oils, and “protect” the oil from degradation. As the scientists explain in a paper published in Plant Biotechnology Journal, such oil-rich duckweed could be easily harvested to produce biofuels or other bioproducts.

The paper describes how the scientists engineered a strain of duckweed, Lemna japonica, to accumulate oil at close to 10 percent of its dry weight biomass. That’s a dramatic, 100-fold increase over such plants growing in the wild—with yields more than seven times higher than soybeans, today’s largest source of biodiesel.

“Duckweed grows fast,” said Brookhaven Lab biochemist John Shanklin, who led the team. “It has only tiny stems and roots—so most of its biomass is in leaf-like fronds that grow on the surface of ponds worldwide. Our engineering creates high oil content in all that biomass.

“Growing and harvesting this engineered duckweed in batches and extracting its oil could be an efficient pathway to renewable and sustainable oil production,” he said.

Bioplastics made of bacteria to reduce plastic waste in oceans

The Nereid Biomaterials team, including Rochester biologist Anne S. Meyer, has created the first ocean instrument made with 3D-printed internal parts composed of bioplastics. The instrument will be replicated and deployed in swarms to enable distributed measurements of the ocean carbon cycle. But because they will be made of bioplastic designed to degrade in oceans, the instruments will not add to the growing problem of (nondegradable) plastic marine pollution. Future applications may extend well beyond ocean instrumentation.
Credit: Melissa Omand / University of Rhode Island

A team of scientists, including Rochester biologist Anne S. Meyer, is developing bioplastics to degrade in oceans.

Plastic waste poses an urgent problem for our planet’s ecosystems, especially our waterways. Millions of tons of plastic waste enter Earth’s oceans every year, and plastic has been found in every part of the ocean, including at the bottom of the deepest ocean trenches.

Although some biodegradable plastics, or bioplastics, have recently been developed, these plastics were intended to break down in industrial compost facilities. In cold, dark ocean environments, they break down very slowly.

What if there were a way to avoid the problem of plastic pollution while still reaping the benefits of plastic’s durability, versatility, and low cost?

In order to tackle this problem, Anne S. Meyer, an associate professor in the Department of Biology at the University of Rochester, worked with marine microbiologist Alyson Santoro at the University of California, Santa Barbara; University of Rhode Island oceanographer Melissa Omand; ecologist Ryan Freedman from the Channel Islands National Marine Sanctuary; and industry partner Mango Materials. Together, the team is developing bioplastics—environmentally friendly plastic materials engineered to degrade in ocean environments.

How the secrets of the ‘water bear’ could improve lifesaving drugs like insulin

A tardigrade, or water bear, floating in water. The tiny organism can endure some of the most extreme conditions on Earth — and even space.
Credit: Schokraie E, Warnken U, Hotz-Wagenblatt A, Grohme MA, Hengherr S, et al. licensed under the Creative Commons Attribution 2.5 Generic license.

UCLA chemist Heather Maynard had to wonder: How do organisms like the tardigrade do it?

This stocky microscopic animal, also known as a water bear, can survive in environments where survival seems impossible. Tardigrades have been shown to endure extremes of heat, cold and pressure — and even the vacuum of space — by entering a state of suspended animation and revitalizing, sometimes decades later, under more hospitable conditions. 

If she could understand the mechanism behind this extraordinary preservation, Maynard reckoned, she might be able to use the knowledge to improve medicines so that they remain potent longer and are less vulnerable to typical environmental challenges, ultimately broadening access and benefiting human health.

It turns out that one of the processes protecting tardigrades is spurred by a sugar molecule called trehalose, commonly found in living things from plants to microbes to insects, some of which use it as blood sugar. For a few select organisms, such as the water bear and the spiky resurrection plant, that can revive after years of near-zero metabolism and complete dehydration, trehalose’s stabilizing power is the secret to their unearthly fortitude.

Driving high? Chemists make strides toward a marijuana breath analyzer

The researchers’ THC-powered fuel cell sensor, with its H-shaped glass chamber.
Credit: Evan Darzi 

A UCLA chemist and colleagues are now a step closer to their goal of developing a handheld tool similar to an alcohol Breathalyzer that can detect THC on a person’s breath after they’ve smoked marijuana.

In a paper published in the journal Organic Letters, UCLA organic chemistry professor Neil Garg and researchers from the UCLA startup ElectraTect Inc. describe the process by which THC introduced, in a solution, into their laboratory-built device can be oxidized, creating an electric current whose strength indicates how much of the psychoactive compound is present.

With the recent legalization or decriminalization of marijuana in many states, including California, the availability of a Breathalyzer-like tool could help make roadways safer, the researchers said. Studies have shown that consumption of marijuana impairs certain driving skills and is associated with a significantly elevated risk of accidents.

In 2020, Garg and UCLA postdoctoral researcher Evan Darzi discovered that removing a hydrogen molecule from the larger THC molecule caused it to change colors in a detectable way. The process, known as oxidation, is similar to that used in alcohol breath analyzers, which convert ethanol into an organic chemical compound through the loss of hydrogen. In most modern alcohol breath analyzer devices, this oxidation leads to an electric current that shows the presence and concentration of ethanol in the breath.

Since their 2020 finding, the researchers have been working with their patent-pending oxidation technology to develop a THC breath analyzer that works similarly. ElectraTect has exclusively licensed the patent rights from UCLA.

Artificial Enzyme Splits Water

Enzyme-like water preorganization in front of a Ruthenium water oxidation catalyst.
Image credit: Team Würthner

Progress has been made on the path to sunlight-driven production of hydrogen. Chemists from Würzburg present a new enzyme-like molecular catalyst for water oxidation.

Mankind is facing a central challenge: it must manage the transition to a sustainable and carbon dioxide-neutral energy economy.

Hydrogen is considered a promising alternative to fossil fuels. It can be produced from water using electricity. If the electricity comes from renewable sources, it is called green hydrogen. But it would be even more sustainable if hydrogen could be produced directly with the energy of sunlight.

In nature, light-driven water splitting takes place during photosynthesis in plants. Plants use a complex molecular apparatus for this, the so-called photosystem II. Mimicking its active center is a promising strategy for realizing the sustainable production of hydrogen. A team led by Professor Frank Würthner at the Institute of Organic Chemistry and the Center for Nanosystems Chemistry at Julius-Maximilians-Universität Würzburg (JMU) is working on this.

AI boosts usability of paper-making waste products

Photo and graphic with birch tree by J. Löfgren

In a new and exciting collaboration with the Department of Bioproducts and Biosystems, researchers in the CEST group have published a study demonstrating how artificial intelligence (AI) can boost the production of renewable biomaterials. Their publication focuses on the extraction of lignin, an organic polymer that together with cellulose makes up the cell walls of plants. As a side-product of papermaking, lignin is produced in large quantities around the world but seldom used as anything other than cheap fuel. Developing valuable materials and chemicals from lignin would consequently be a big step towards a sustainable society.

A key challenge for the valorization of lignin is to find the right experimental extraction conditions. These include things like the temperature in the hot-water reactor where the wood is processed, the reaction time and the ratio of wood to water. These conditions not only affect the amount of lignin that can be extracted, but also the physical and chemical properties of the extracted lignin itself. Therefore, knowing how to choose the right experimental conditions is important since the more lignin can be extracted the better, and different lignin-based products may require lignin with different properties.

A Different Kind of Therapy for Stroke

Stroke folders and labels at the Emergency Department at UConn Health in Farmington on Sept. 29, 2020.
Photo Credit: Peter Morenus/UConn

Stroke deprives the brain of oxygen and energy, causing a cascade of spreading cell death. Blocking a specific receptor could contain the damage, researchers from UConn Health and the National Institutes of Health (NIH) report in the Journal of Medicinal Chemistry.

A stroke occurs when a blood vessel in the brain is either ruptured or clogged. The loss of blood flow deprives part of the brain of oxygen, and cells begin to die within minutes. Every 40 seconds someone in the US has a stroke, according to the Centers for Disease Control and Prevention. That’s more than 795,000 people every year. More than half of the survivors will have permanent difficulties walking, talking and caring for themselves.

The faster someone suffering from a stroke gets medical help, the more likely they are to avoid serious lasting disability. Restoring blood flow to the brain as fast as possible to avoid cell death is critical.

But other factors besides blood flow can also contribute to cell death in brain during a stroke. For example, brain cells store lots of energy in the form of the molecule ATP. When a brain cell dies, it releases all of its stored ATP. The spilled ATP triggers a receptor called P2X4 on neighboring brain cells. If the P2X4 receptor is overstimulated, it can trigger a rush of calcium ions that can activate cell death enzymes and set off a destructive cycle of brain damage.

Process converts polyethylene bags, plastics to polymer building blocks

Plastics made from polyethylene (white strands), such as the milk bottle shown in background, can now be broken down into smaller molecules — propylene — that are valuable for making another type of plastic, polypropylene. Click image for more detailed caption.
Graphic credit: Brandon Bloomer, UC Berkeley

Polyethylene plastics — in particular, the ubiquitous plastic bag that blights the landscape — are notoriously hard to recycle. They’re sturdy and difficult to break down, and if they’re recycled at all, they’re melted into a polymer stew useful mostly for decking and other low-value products.

But a new process developed at the University of California, Berkeley, and Lawrence Berkeley National Laboratory (Berkeley Lab) could change all that. The process uses catalysts to break the long polyethylene (PE) polymers into uniform chunks — the three-carbon molecule propylene — that are the feedstocks for making other types of high-value plastic, such as polypropylene.

The process, admittedly in the early stages of development, would turn a waste product — not only plastic bags and packaging, but all types of PE plastic bottles — into a major product in high demand. Previous methods to break the chains of polyethylene required high temperatures and gave mixtures of components in much lower demand. The new process could not only lower the need for fossil fuel production of propylene, often called propene, but also help fill a currently unmet need by the plastics industry for more propylene.

How fish survive the extreme pressures of life in the oceans

Photo credit: Milos Prelevic

Scientists have discovered how a chemical in the cells of marine organisms enables them to survive the high pressures found in the deep oceans.

The deeper that sea creatures live, the more inhospitable and extreme the environment they must cope with. In one of the deepest points in the Pacific - the Mariana Trench, 11 kilometers below the sea surface - the pressure is 1.1 kbar or eight tons per square inch. That is a 1,100-fold increase of the pressure experienced at the Earth’s surface.

Under normal or atmospheric pressure, water molecules form a tetrahedron-like network. At high pressure, though, the network of water molecules begins to distort and change shape. When this happens to the water inside living cells, it prevents vital bio-chemical processes from taking place - and kills the organism.

Our study provides a bridge between water under pressure at the molecular level and the wonderful ability of organisms which thrive under high pressure in depths of the oceans.

In reporting their findings, the researchers in Leeds have for the first time been able to provide an explanation of how a molecule found in the cells of marine organisms counteracts the effect of external pressure on the water molecules.

Novel Carrier Doping in p-type Semiconductors Enhances Photovoltaic Device Performance by Increasing Hole Concentration

The carrier concentration and conductivity in p-type monovalent copper semiconductors can be significantly enhanced by adding alkali metal impurities, as shown recently by Tokyo Tech researchers. Doping with isovalent and larger-sized alkali metal ions effectively increased the free charge carrier concentration and the mechanism was unraveled by their theoretical calculations. Their carrier doping technology enables high carrier concentration and high mobility p-type thin films to be prepared from the solution process, with photovoltaic device applications.

Perovskite solar cells have been the subject of much research as the next generation of photovoltaic devices. However, many challenges remain to be overcome for the practical application. One of them concerns the hole transport layer (p-type semiconductor) in photovoltaic cells that carries holes generated by light to the electrode. In conventional p-type organic transport semiconductors, hole dopants are chemically reactive and degrade the photovoltaic device. Inorganic p-type semiconductors, which are chemically stable, are promising alternatives, but fabrication of conventional inorganic p-type semiconductors requires high temperature treatment. In this regard, the p-type inorganic semiconductors that can be fabricated at low temperatures and have excellent hole transport ability have been desired.

Inorganic p-type copper iodide (CuI) semiconductor is a leading candidate for such hole transport materials in photovoltaic device applications. In this material, native defects give rise to charge imbalance and free charge carriers. However, the overall number of defects is generally too low for satisfactory device performance.