Category: Chemistry

by Nick William Smith, Andrew John Fletcher and Warren McNabb, The Conversation

Have you ever looked down at your breakfast, lunch or dinner and considered where the ingredients traveled from to reach your plate?

A basic sandwich in New Zealand can easily represent five countries: an Australian wheat and Indian sesame seed roll, Danish salami, local lettuce and cheese, seasoned with Vietnamese pepper.

And because your food travels a long way to reach you, so does your nutrition.

Research on global food trade—particularly trade in cereals—has a long history. More recently, researchers have begun considering the nutrients—energy, protein, vitamins, minerals—that move around the world within traded food.

As we learn more about the global trade in nutrients we can build a better picture of how these key dietary ingredients are distributed, and how they affect global population health.

Mapping global nutrient trade

The Sustainable Nutrition Initiative undertakes modeling research on the links between global food production and the nutrition of the global population.

Working with researchers at the University of São Paulo and State University of Campinas in Brazil, we have now published a broader analysis of global nutrient trade over time and its impact on health.

It shows the variation in nutrient trade between countries with differing wealth, and some positive links between nutrient trade and health.

Our team built a large data set of all flows of food for human consumption between 254 countries from 1986 to 2020. From this, we worked out the flows of 48 essential nutrients over that period.

As this is too much information for a single scientific paper, the team built an interactive app to let anyone explore the data.

The paper itself focused on a few key nutrients: protein, calcium, iron and vitamins A and B12. These are often used in analyses of food security (having reliable access to enough affordable, nutritious food) because of their importance to human health.

Some of these nutrients are under-supplied in many parts of the world, particularly low-income countries. At the same time, nutrient trade over the 35 years we analyzed has grown rapidly, as shown in the chart below for vitamin B12.

The wealth and nutrient gap

High-income countries were the biggest importers of vitamin B12, but also the other nutrients analyzed, largely from trade with other high-income countries. This is despite those countries having only around 15% of the global population.

In contrast, low-income countries have little involvement in global trade of any nutrients. This limits their ability to improve dietary diversity and quality through food from outside their borders.

Most of New Zealand’s trading partners are in the higher-income brackets. Milk and meat dominate New Zealand protein exports, with China the major partner (see chart below).

The quantity of protein exported would meet the needs of nearly seven times New Zealand’s own population. In a country like China, of course, this is only a small fraction of the population.

In contrast, nearly 60% of New Zealand’s protein imports comes from Australia, largely in wheat and wheat products. And New Zealand imports enough protein to meet around half its population’s need.

We also analyzed the socioeconomic, demographic and health outcome data potentially associated with food consumption patterns and nutrient trade.

The findings suggest higher involvement in nutrient trade networks was significantly associated with improvements in infant mortality rates, lower prevalence of anemia in women of reproductive age, and greater life expectancy.

Food security and nutrition

It is concerning to see the low involvement of low-income countries in nutrient trade, particularly given the benefits it can bring for population health.

Our research provides context for how important traded nutrients are in meeting national population requirements. This knowledge can be used to identify weaknesses in the global food system, and which shocks (climatic, political or biological) might have the greatest consequences for nutrition.

These data can then be combined with other knowledge and modeling of food production, distribution and consumption at national levels to give a more complete view of food systems.

Food trade plays a key role in fostering food security and good nutrition. The trade has grown rapidly in both quantity and economic value over the past 35 years. Understanding its importance for healthy nutrition is essential.

by Liu Jia, Chinese Academy of Sciences

A research group led by Prof. Wan Yinhua from the Institute of Process Engineering of the Chinese Academy of Sciences has developed a catalyst with dual photocatalytic and biomimetic catalytic activity for the production of hydrogen peroxide (H₂O₂).

The strategy involves loading gold nanoparticles (AuNPs) onto graphite carbon nitride (GCN) nanosheets using polyethyleneimine (PEI) as a “bridge.” The study was published in the Chemical Engineering Journal.

H₂O₂, recognized as an environmentally friendly oxidant, is extensively used in various fields such as medical treatment, environmental restoration, fine chemicals, and electronics industries. However, the conventional method of H₂O₂ production relies on the anthraquinone process, which has several drawbacks including high energy consumption, the use of organic solvents, and safety hazards. Therefore, there is a pressing need to develop a sustainable and eco-friendly manufacturing process for H₂O₂.

Solar-driven photocatalysis is a promising alternative strategy for H₂O₂ production, and GCN is a popular choice in the field of photocatalysis due to its straightforward synthesis, cost-effectiveness, stable physical and chemical properties, and broad light absorption spectrum. However, GCN nanosheets alone have limited performance in photocatalytic H₂O₂ production in pure water due to the high energy barrier of water dissociation and low separation efficiency of charge carriers.

Hole sacrificial agents (acting as electron donors) such as ethanol, isopropanol, and benzyl alcohol are commonly used to improve the selectivity of oxygen reduction. However, the addition of organic agents has adverse environmental impacts, which is not conducive to the sustainability of H₂O₂ production. Therefore, it is crucial to engineer a GCN material with enhanced electron-hole pair separation efficiency to facilitate water oxidation and oxygen reduction.

“Inspired by photo-enzyme-coupled catalytic system in chloroplasts, we developed a composite catalyst by loading AuNPs (enzyme mimics) on GCN (photocatalyst) nanosheets using PEI as the ‘bridge’ (PEI-GCN/Au),” Prof. Wan said.

The introduction of PEI and AuNPs helps adjust the electronic structure of GCN, facilitating the rapid separation of photogenerated carriers. The surface plasmon resonance of AuNPs, when excited by incident light, promotes the activation of glucose molecules, elevating their reactivity with O₂ and improving the glucose oxidase-mimicking catalytic production of H₂O₂. The grafting of PEI and the addition of glucose enhance the O₂ adsorption on the catalyst surface.

The PEI-GCN/Au composite demonstrates exceptional H₂O₂ production efficiency (270 μmol g^-1 h^-1) under visible light irradiation, using only glucose, H₂O and O₂ as reactants. As a result, both the biomimetic catalytic and photocatalytic reduction of O₂ to H₂O₂ are enhanced, achieving a significant synergistic enhancement effect of 175%.

“This work establishes a paradigm of coupling biomimetic catalysis and photocatalysis for co-production of chemicals. It not only provides insights into the development of materials for efficient H₂O₂ production, but also introduces an innovative concept for integrating biocatalysis and photocatalysis,” said Prof. Luo Jianquan, the corresponding author of this study.

More information: Huiru Zhang et al, Biomimetic-photo-coupled catalysis for boosting H2O2 production, Chemical Engineering Journal (2024). DOI: 10.1016/j.cej.2024.149183

Provided by Chinese Academy of Sciences 

by Max Planck Society

The production of aluminum generates around 180 million tons of toxic red mud every year. Scientists at the Max-Planck-Institut für Eisenforschung, a center for iron research, have now shown how green steel can be produced from aluminum production waste in a relatively simple way. In an electric arc furnace similar to those used in the steel industry for decades, they convert the iron oxide contained in the red mud into iron using hydrogen plasma.

With this process, almost 700 million tons of CO₂-free steel could be produced from the 4 billion tons of red mud that have accumulated worldwide to date—which corresponds to a good third of annual steel production worldwide. As the Max Planck team shows, the process would also be economically viable.

According to forecasts, demand for steel and aluminum will increase by up to 60% by 2050. Yet the conventional production of these metals has a considerable impact on the environment. Eight percent of global CO₂ emissions come from the steel industry, making it the sector with the highest greenhouse gas emissions. Meanwhile, aluminum industry produces around 180 million tons of red mud every year, which is highly alkaline and contains traces of heavy metals such as chromium.

In Australia, Brazil and China, among others, this waste is at best dried and disposed of in gigantic landfill sites, resulting in high processing costs. When it rains heavily, the red mud is often washed out of the landfill, and when it dries, the wind can blow it into the environment as dust.

In addition, the highly alkaline red mud corrodes the concrete walls of the landfills, resulting in red mud leaks that have already triggered environmental disasters on several occasions, for example in China in 2012 and in Hungary in 2010. In addition, large quantities of red mud are also simply disposed of in nature.

Potential to save 1.5 billion tons of CO₂ in the steel industry

“Our process could simultaneously solve the waste problem of aluminum production and improve the steel industry’s carbon footprint,” says Matic Jovičevič-Klug, who played a key role in the work as a scientist at the Max-Planck-Institut für Eisenforschung. In a study published in the journal Nature, the team shows how red mud can be utilized as a raw material in the steel industry. This is because the waste from aluminum production consists of up to 60% iron oxide.

The Max Planck scientists melt the red mud in an electric arc furnace and simultaneously reduce the contained iron oxide to iron using a plasma that contains 10% hydrogen. The transformation, known in technical jargon as plasma reduction, takes just ten minutes, during which the liquid iron separates from the liquid oxides and can then be extracted easily. The iron is so pure that it can be processed directly into steel.

The remaining metal oxides are no longer corrosive and solidify on cooling to form a glass-like material that can be used as a filling material in the construction industry, for example. Other research groups have produced iron from red mud using a similar approach with coke, but this produces highly contaminated iron and large quantities of CO₂. Using green hydrogen as a reducing agent avoids these greenhouse gas emissions.

“If green hydrogen would be used to produce iron from the 4 billion tons of red mud that have been generated in global aluminum production to date, the steel industry could save almost 1.5 billion tons of CO₂,” says Isnaldi Souza Filho, Research Group Leader at the Max-Planck-Institut für Eisenforschung.

An economical process, including with green hydrogen and electricity

The heavy metals in the red mud can also be virtually neutralized using the process. “After reduction, we detected chromium in the iron,” says Jovičevič-Klug. “Other heavy and precious metals are also likely to go into the iron or into a separate area. That’s something we’ll investigate in further studies. Valuable metals could then be separated and reused.”

Additionally, heavy metals that remain in the metal oxides are firmly bound within them and can no longer be washed out with water, as can happen with red mud.

However, producing iron from red mud directly using hydrogen not only benefits the environment twice over; it pays off economically too, as the research team demonstrated in a cost analysis. With hydrogen and an electricity mix for the electric arc furnace from only partially renewable sources, the process is worthwhile, if the red mud contains 50% iron oxide or more.

If the costs for the disposal of the red mud are also considered, only 35% iron oxide is sufficient to make the process economical. With green hydrogen and electricity, at today’s costs—also taking into account the cost of landfilling the red mud—a proportion of 30 to 40% iron oxide is required for the resulting iron to be competitive on the market.

“These are conservative estimates because the costs for the disposal of the red mud are probably calculated rather low,” says Isnaldi Souza Filho. And there’s another advantage from a practical point of view: electric arc furnaces are widely used in the metal industry—including in aluminum smelters—as they are used to melt down scrap metal. In many cases, the industry would therefore need to invest only a little to become more sustainable.

“It was important for us to also consider economic aspects in our study,” says Dierk Raabe, Director at the Max-Planck-Institut für Eisenforschung. “Now it’s up to the industry to decide whether it will utilize the plasma reduction of red mud to iron.”

by Ziyan Yang

Electrocatalytic reduction of carbon dioxide (CO₂) is considered as an effective strategy for mitigating the energy crisis and the greenhouse effect. Among the multiple reduction products, CO is regarded as having the highest market value as it is a crucial feedstock for Fischer-Tropsch process which can synthesize high-value long-chain hydrocarbons.

Since the carbon dioxide reduction reaction (CO₂RR) has complex intermediates and multiple proton-coupled electron transfer processes, improving the reaction activity and products selectivity remain two great challenges.

Single-atom catalysts (SACs) have the advantages of high atom utilization, tunable coordination structure and excellent catalytic performance. In addition, due to the special electronic structure of nickel metal, it is more likely to lose electrons to form empty outermost d-orbitals and exhibit high activity and selectivity for CO₂RR to generate CO.

A team of scientists have summarized the considerable progress of Ni SACs in recent years. Their work is published in Industrial Chemistry & Materials.

“Designing novel catalysts to improve the activity and selectivity of CO₂RR is crucial for conquering the problem of energy crisis and environmental pollution,” said Yuhang Li, a Professor at East China University of Science and Technology, China,

“In this mini-review, we introduced three strategies used to improve the catalytic performance of Ni SACs, including different structures of supports, coordination structure regulation, and surface modification. In the end, we also summarized the existing challenges of Ni SACs and provided an outlook on future development in this field.”

SACs downsize the active sites to atomic scale and therefore get extraordinary electronic structure, powerful metal-support interactions, low-coordinated metal atoms, and maximum atom utilization at the same time. Hence, the application of SACs in CO₂RR could effectively control the distribution of products and alleviate the cost of products separation.

“Some research based on crystal-field theory has indicated that the d-orbital electronic configurations of central metals are significant to the selectivity and activity of CO₂RR,” Li said.

“In the case of nickel as the central metal atom, it is more likely to form the vacant outermost d-orbital to facilitate the electron transfer between the C atom of CO₂ and the Ni atom. Therefore, the absorbed CO₂ molecules can be efficiently activated. Ni SACs can also minimize the reaction potential of CO₂-CO conversion, which is of great importance to enhance the selectivity towards CO.”

“Ni SACs have achieved continuous progress in recent years. From a microscopic point of view, the design strategies include choosing different substrates, regulating the coordination structure and modifying the catalyst surface. The electronic structure of the active center is the most crucial factor affecting catalytic performance,” Li said.

There is still tremendous potential for Ni SACs in future designs and applications. Precise modulation of the microstructure provides more active sites and therefore further enhances the performance of Ni SACs. Optimization of the electrolytic cells and development of more types of electrolytes can expand the range of Ni SACs applications and enable large-scale commercialization in the future.

In addition, researchers think that developing more in-situ techniques to gain deeper insights into the relationship between material structure and properties can provide valuable guidance for designing higher-value Ni SACs.

“In this mini-review, our main goal is to provide readers with the current research progress in Ni SACs in CO₂RR and to show our insights into the design and application of single-atom catalysts,” Li said.

The research team includes Ziyan Yang, Rongzhen Chen, Ling Zhang, Yuhang Li, and Chunzhong Li from East China University of Science and Technology.

by Laurie Fickman, University of Houston

A million years ago, the oldest known species to walk upright like a human, the Homo erectus, had a human-like fascination with crystals. Historians can even pin down the possible reasons—crystals didn’t look like anything around at the time—trees, valleys, mountains. Crystals were a material to ponder, a fascinating diversion for the mind.

To this day, the human preoccupation with the magic of crystals continues to fill the mind’s eye of scientists who have developed ways to use crystals for everything from malaria cures to solar cells and semiconductors, catalysts and optical elements. Over the years crystals have become crucial constituents of the technologies that enable modern civilization.

University of Houston researcher Peter Vekilov and Frank Worley Professor of Chemical and Biomolecular Engineering, have published in PNAS an answer to how crystals are formed and how molecules become a part of them.

“For decades crystal growth researchers have dreamt of elucidating the chemical reaction between incoming molecules and the unique sites on a crystal surface that accept them, the kinks,” said Vekilov. “The mechanism of that reaction, i.e., the characteristic time scale and length scale, possible intermediates and their stabilities, has remained elusive and subject to speculation for over 60 years.”

The main obstacle to deeper understanding has been the lack of data on how molecules join in, connected to the complicated process of moving from the solution to where they grow.

To unravel the chemical reaction between a molecule that dissolves in liquid (solute) and a kink, Vekilov mobilized two transformational strategies, one using full organic pairs and the second, using four solvents with distinct structures and functions. Working with the molecules, he combined state-of-the-art experimental techniques including time-resolved in situ atomic-force microscopy at near-molecular resolution, X-ray diffraction, absorption spectroscopy and scanning electron microcopy.

That’s when Vekilov made a revolutionary discovery: Incorporation into kinks may occur in two steps divided by an intermediate state and the stability of this middle state is key in how crystals grow. It basically decides how fast or slow the crystals form because it affects how easily things can join in during the process

Though the new discoveries don’t date back to Homo sapien times, they do solve a 40-year-old riddle for Vekilov.

“The notions of an intermediate state and its decisive role in crystal growth refute and replace the dominant idea in the field, brought up by A.A. Chernov, my Ph.D. advisor, that the activation barrier for growth is determined by the solute-solvent interactions in the solution bulk,” he said.

The new paradigm of two step incorporation, mediated by an intermediate state, could help in understanding how small parts in a liquid can influence the detailed shapes of crystals found in nature.

“Equally important, this paradigm will guide the search for solvents and additives that stabilize the intermediate state to slow down the growth of, for instance, undesired polymorphs,” Vekilov said.

Vekilov’s team includes Jeremy Palmer, Ernest J and Barbara M Henley Associate Professor of chemical and biomolecular engineering; former graduate students Rajshree Chakrabarti and Lakshmanji Verma; and Viktor G. Hadjiev, Texas Center for Superconductivity at UH.

More information: Rajshree Chakrabarti et al, The elementary reactions for incorporation into crystals, Proceedings of the National Academy of Sciences (2024). DOI: 10.1073/pnas.2320201121

Provided by University of Houston 

From smartphones to wind turbines, rare earth elements (REEs) are an essential part of the hardware in many advanced technologies. These elements, which include the lanthanides along with scandium and yttrium, are the backbone of industries that rely on unique properties such as luminescence, magnetism and catalytic ability. In fact, as our world moves toward more sustainable energy solutions and increasingly sophisticated technologies, the demand for REEs is projected to grow substantially.

There’s one catch, however: REEs are difficult to extract and even harder to separate. These elements, despite their name, aren’t actually rare in terms of abundance. What makes them “rare” is their dispersion throughout the Earth’s crust and their chemical similarities, which make them incredibly challenging to isolate from one another.

Current separation methods—largely reliant on toxic solvents like kerosene—are not only inefficient, but also harmful to people and the environment. Additionally, while the U.S. once dominated REE mining and production, environmental restrictions on current separation methods have limited domestic production.

Kathleen Stebe, Richer & Elizabeth Goodwin Professor in Chemical and Biomolecular Engineering (CBE), is tackling this challenge head-on with a collaborative group of researchers across five institutions under the support of a grant from the Department of Energy. Stebe is leading a groundbreaking research initiative that aims to create an eco-friendly, bioinspired process for separating REEs that would also avoid shipping semi-processed REEs to other countries for purification.

“Current separation methods use kerosene and extractants-molecules that bind the REE cations, a positively charged particle, that create issues, both environmentally and in terms of efficiency,” says Stebe. “The separation process is not selective enough to efficiently separate lanthanides, meaning that it has to be repeated many times to achieve REEs in sufficient purity. The whole method is cumbersome and creates unnecessary waste.”

Stebe, along with a team of researchers from Penn, the City College of New York, the University of Illinois Chicago, Northwestern University and the University of Chicago, look to human biology to find the molecule best suited for the job of separation: peptides.

Bioinspired interfaces: Drawing on nature’s expertise

In nature, organisms have evolved proteins that selectively bind to specific ions, despite their similar properties. A perfect example of this is calcium-binding proteins in the human body, which can distinguish between calcium and magnesium ions, even though both have the same charge.

“We are applying this concept to create a similar level of selectivity for rare earth elements,” says collaborator E. James Petersson, professor of chemistry, biochemistry and biophysics at Penn’s School of Arts & Sciences. “By using peptide-based molecules—specifically, a truncated version of the EF-hand motif, which is naturally found in calcium-binding proteins—we are designing molecules that can selectively bind to specific rare earth elements.”

This EF-hand motif refers to the structure and mechanism through which these naturally occurring proteins and peptides are able to differentiate between two very similar molecules.

“The structure resembles a hand,” says Stebe, “and each ‘finger’ of the hand is laden with a carboxyl or carbonyl group that binds to cations floating around in solution. It’s a beautiful and complex structure that can recognize the nuanced and subtle differences between two nearly indistinct cations, and then capture and hold onto whichever cation it is ‘looking’ for. This is extremely important for separating REEs, which differ in size by only one-tenth of an angstrom.”

In the team’s recent study published in the Proceedings of the National Academy of Sciences, they found that EF-hand-containing peptides could bind to the peptide-cation complex and capture it at the aqueous-air interface. The vision includes using bubbles to separate specific lanthanides from a mixture. Once bound to the peptides in an aqueous solution, the REEs will rise to the surface, where they are trapped in a foam at the water-air interface, a separation technique called ion foam flotation.

“My primary area of research is in interfacial science, studying the adsorption of surface-active molecules—surfactants and soap molecules—to the air-water interface,” says co-author Charles Maldarelli, professor of chemical engineering at The City College of New York. “This study gave me the opportunity to apply my expertise to the adsorption of peptides and peptide-metal complexes at the interface.”

Felipe Jimenez-Angeles, research associate professor at Northwestern University, performed many of the molecular dynamics simulations in this study. “I am fascinated that these peptides can separate ions that only differ by a few tenths of an Angstrom in diameter via the differences in the electrostatic forces at the atomic scale. The water-soluble peptide reconfigures when it captures the ion and becomes insoluble in water, resulting in its adsorption to the air-water interface.”

The team’s next steps in this research will be investigating how to scale this process, allowing them to isolate target REEs and collect them at usable quantities in a way that is much more efficient and environmentally friendly.

The collaborative effort behind the innovation

What makes this project truly innovative is the collaboration across multiple universities and disciplines. Each institution brings unique expertise to the project, from synthetic chemistry to surface material properties, and even X-ray experiments.

“This is really the first time my lab has used biology to solve chemistry problems,” says Petersson. “Normally, we focus on creating chemical probes to study biology, often looking at neurodegenerative disorders like Parkinson’s disease. But the experience of working on this project has inspired me to explore other biological approaches to chemistry, including adapting disease-related proteins for applications in other fields like energy and sustainability.”

“I have long been interested in molecular interface interactions,” adds Ivan Dmochowski, Professor of Chemistry in Penn’s School of Arts & Sciences. “As an undergraduate, I made molecules that react with the surface of glass and gold, and studied the resulting monolayers that formed. Later I started looking at proteins at the air-water interface.”

Other key senior faculty involved in the research include Monica Olvera de la Cruz from Northwestern University, Raymond Tu from CCNY, Mark Schlossman from the University of Illinois at Chicago, and Daeyeon Lee, Ravi Radhakrishnan and Cesar de la Fuente at the University of Pennsylvania.

“It has been rewarding to both contribute to and learn from this effort,” continues Dmochowski. “To solve really challenging, societally relevant problems in 2025, we will need a wide range of technical expertise, and I am excited to continue working with this team of collaborators to do that.”

Looking ahead: The future of rare earth element recovery

As Stebe’s team continues their work, they are focused on fine-tuning the selectivity of the peptides and optimizing the process for bulk production. Their next steps include using specialized peptides designed by Petersson to enhance the fluorescence of the system, allowing for more precise tracking of the binding events. They also plan to use physics data to inform additional opportunities for improved specificity and look into developing new, synthetic molecules to make this method even more cost-effective and environmentally friendly.

“This is just the beginning,” says Stebe. “We have a lot of exciting new directions to explore, from using synthetic molecules instead of peptides to creating even more selective binding structures. The potential impact of this work goes far beyond just rare earth elements—it could revolutionize the way we approach material separation across many industries.”

More information: Luis E. Ortuno Macias et al, Lanthanide binding peptide surfactants at air–aqueous interfaces for interfacial separation of rare earth elements, Proceedings of the National Academy of Sciences (2024). DOI: 10.1073/pnas.2411763121

Journal information: Proceedings of the National Academy of Sciences 

Provided by University of Pennsylvania 

by Melissa Pappas, University of Pennsylvania

From caffeine to penicillin, natural products have become a mainstay in modern society, and are used for numerous applications, such as medicine and pesticides. There are tens of thousands of untapped natural products, but identifying new compounds with bioactivity can be difficult, especially when produced in low quantities.

To overcome this, researchers at the University of Illinois Urbana-Champaign have developed FAST-NPS, a new method to accelerate the discovery and scale up of bioactive natural products found in Streptomyces. The work is published in the journal Cell Systems.

Natural products are chemicals produced by living organisms that are either essential for the organism to survive or provide secondary functions such as protection from infection or predators. The discovery of natural products derived from bacteria, fungi, and plants has been particularly advantageous for the development of lifesaving medicines, including antibiotics like erythromycin, daptomycin, and vancomycin, which have been isolated from Streptomyces.

With advancements in computational technology and genomic sequencing, researchers can use microbial genome mining to more efficiently discover new natural products, compared to traditional methods that require isolation directly from organisms. But there are still improvements that can be made to these processes, because not all natural products demonstrate bioactive properties and many are produced in low quantities, making them hard to detect.

Natural products are structurally diverse, coming in a variety of shapes and sizes that can often be too complex for chemists to synthesize. However, nature proves to be the best chemist, using numerous enzymes to build these natural products in microorganisms. The genes that encode the required enzymes are often located together in the genome to form so-called biosynthetic gene clusters, BGCs. Using bioinformatics and machine learning techniques, researchers can identify BGCs in microbial genomes to discover new natural products.

“In this work, we try to address two challenges in natural product discovery. The first challenge is how we can efficiently identify new compounds that are bioactive,” said Huimin Zhao, the Steven L. Miller Chair of Chemical and Biomolecular Engineering (BSD theme leader/CABBI/CGD/MMG). “The second challenge is how we can scale up our CAPTURE method using our robotic system.”

To tackle the first challenge, the research study, led by postdoctoral researcher and first author of the paper Yujie Yuan, leveraged self-resistance genes.

“We are using the self-resistance genes as markers to prioritize BGCs of natural products with bioactivity,” Yuan said.

Self-resistance genes are an evolutionary response to shield organisms from any negative effects that could be caused by their own natural products. So the self-resistance genes in the BGCs serve as a predictor of the bioactivity of the corresponding natural products, therefore improving the efficiency of the discovery process by narrowing the pool of BGCs to further pursue and test.

After identifying a target BGC using the Antibiotic Resistant Target Seeker tool, ARTS, its genes are captured from the microbial genome and inserted into bacteria that can synthesize the natural product. Zhao’s group had previously reported a high-efficiency direct cloning method coupled with heterologous expression to accomplish this.

“In the past, we developed the CAPTURE method, which allows us to clone large biosynthetic gene clusters from microbial genomes with high efficiency. Although the process is very efficient, it is tedious and involves a lot of manual work,” Zhao said.

The team adapted their CAPTURE and heterologous expression methods into a fully automated, scalable, high-throughput platform, called FAST-NPS, for discovering bioactive natural products in Streptomyces. FAST-NPS integrates seamlessly with the ARTS tool.

By fully automating this process using the Illinois Biological Foundry for Advanced Biomanufacturing, iBioFAB, they are able to eliminate this tedious manual labor and increase the number of BCGs they can pursue in parallel. In a process that takes almost a month from start to finish, automation increases the capability to clone and express BGCs from about ten at a time to several hundred at a time.

“We spent a lot of time and effort to develop the automation workflow. This was a big challenge because we had to develop each component, from PCR and RNA transcription to bacterial transformation and heterologous expression,” Yuan said. “I am very proud of our CAPTURE method and am excited to report this more powerful version for the discovery of bioactive compounds.”

The team’s efforts paid off because the proof-of-concept demonstrated a 95% success rate when they cloned 105 BGCs from 11 Streptomyces strains. Further, they identified five promising BGCs, and all five proved to produce bioactive compounds.

But moving forward, Zhao says that there is still room for improvement. “While we had a 100% success rate for discovering bioactive compounds, five is a small number because we still need to improve the success rate of the heterologous expression. We cloned more than 100 biosynthetic gene clusters, and only 12 were functionally expressed. So, this is a challenge that we will try to address.”

More information: Yujie Yuan et al, Self-resistance-gene-guided, high-throughput automated genome mining of bioactive natural products from Streptomyces, Cell Systems (2025). DOI: 10.1016/j.cels.2025.101237

Journal information: Cell Systems 

Provided by University of Illinois at Urbana-Champaign 

Much of cell behavior is governed by the actions of biomolecular condensates: building block molecules that glom together and scatter apart as needed. Biomolecular condensates constantly shift their phase, sometimes becoming solid, sometimes like little droplets of oil in vinegar, and other phases in between.

Understanding the electrochemical properties of such slippery molecules has been a recent focus for researchers at Washington University in St. Louis.

In research published in Nature Chemistry, Yifan Dai, assistant professor of biomedical engineering at the McKelvey School of Engineering, shares the rules involving the intracellular electrochemical properties that affect movement and chemical activities inside the cell and how that might impact cell processes as a condensate ages. The research can inform the development of treatments for diseases like amyotrophic lateral sclerosis (ALS) or cancer.

Extracellular flow—the movement of ions between cell membrane channels—is well studied, but little was known about those same electrochemical fields at play inside the cell.

“In the past century, people have learned a lot regarding electrochemical effects caused by extracellular environmental perturbances. However, in the intracellular world, we do not know much yet,” said Dai.

This work is one of the very first steps to writing those rules. Dai and collaborators from Stanford University, including Professors Guosong Hong and Richard N. Zare, show that condensation and the non-equilibrium process after condensation is itself a way to regulate the electrochemical dynamics of the environments.

Imagine a giant conference hall with lots of little groups of people looking at posters, constantly shifting in and out to different exhibits. Some of those people might want others to follow them to another exhibit or call attention to a different subject and bring others with them.

This is how condensates work, going where they stick, affecting the movements of other condensates with their electrical potentials, and changes to the pH of the surrounding environment. Playing with the surface of those condensates can also affect the electrical potentials, as Dai and colleagues found.

They determined that electrochemical potential is also regulated by “aging-associated intermolecular interactions and interfacial effects.”

Think about that conference hall of people. Over the course of a full day, those interactions are less optimal as the individuals get tired and experience stress.

“The surface of the condensate is going to change during the aging process,” Dai said.

Back in the molecular realm, these “aging-associated” interactions can lead to dysfunction and diseases like ALS and Alzheimer’s, so understanding how to potentially interrupt that could yield medical treatments.

They were able to adjust electrical potentials by modifying the surface of a condensate. By measuring the alignment of the molecule, they could also determine its surface potential for ion flow, and most importantly, find ways to manipulate those surface signals to push healthy biological reactions.

“Hopefully, this work can shed light on the concept that condensate is not just about biomolecules,” Dai said.

More information: Wen Yu et al, Aging-dependent evolving electrochemical potentials of biomolecular condensates regulate their physicochemical activities, Nature Chemistry (2025). DOI: 10.1038/s41557-025-01762-7

Journal information: Nature Chemistry 

Provided by Washington University in St. Louis 

Tryptamine psychoactive substances, such as α-methyltryptamine (AMT), are monoamine alkaloids characterized by an indole ring structure. Rapid, highly sensitive, and specific identification of trace amounts of AMT is crucial for maintaining social stability and ensuring public safety. However, accurately detecting AMT using specific fluorescent methods is challenging due to the presence of similar amine groups and benzene rings in various other amines.

To address this challenge, a research team led by Prof. Dou Xincun from the Xinjiang Technical Institute of Physics and Chemistry of the Chinese Academy of Sciences (CAS) has developed a novel molecular probe strategy to enhance detection sensitivity and selectivity for AMT.

Their findings, published in Analytical Chemistry, emphasize tuning the electron-withdrawing strength of the π-conjugate bridge to improve the reactivity of Schiff base-based fluorescence probes with amines.

In this study, researchers developed three tricyanofuran (TCF)-based probes with different π-conjugated bridges—benzene, benzothiadiazole, and 2,5-dibromobenzene—tailored for amine-containing analytes. Among these, the aldehyde group in the probe with −C₆H₂Br₂ as the π-conjugate bridge, denoted as BrFS-TCF, showed the highest electrostatic potential, making it the most effective for AMT detection due to its superior reactivity.

The optimized probe demonstrated remarkable performance, achieving a fluorescent detection limit of 13 nM, a colorimetric detection limit of 132 nM, and a response time of less than 0.1 seconds. Additionally, the integration of a convolutional neural network algorithm enabled the probe to distinguish AMT from other primary amines, further enhancing its specificity.

Moreover, the probe’s reliability was validated through the detection of trace AMT in artificial saliva and solid residues, showcasing its potential for real-world applications.

This innovative probe design and regulation strategy not only provides a new approach for the specific identification and discrimination of primary amine-containing drugs but also advances the development of methodologies for detecting trace hazards and illicit substances.

More information: Zhenzhen Cai et al, Precise Electron-Withdrawing Strength Regulation of π-Conjugate Bridge-Boosted Specific Detection toward α-Methyltryptamine, Analytical Chemistry (2025). DOI: 10.1021/acs.analchem.4c05950

Journal information: Analytical Chemistry 

Provided by Chinese Academy of Sciences 

by Li Yali, Chinese Academy of Sciences

Synthetic cannabinoids, a class of new psychoactive substances, bind to cannabinoid receptors CB1 and CB2 much more strongly than tetrahydrocannabinol (THC) and cannabidiol (CBD), raising public health concerns due to their toxicity and addiction risk.

Current detection methods mainly use advanced techniques like high-performance liquid chromatography-mass spectrometry (HPLC-MS), gas chromatography-mass spectrometry (GC-MS), and nuclear magnetic resonance (NMR), which are accurate but time-consuming and require complex equipment.

In contrast, visual detection methods such as colorimetry and fluorescence are quicker and easier to interpret, making them better for on-site use. However, there is still a need for visual detection techniques specifically targeting MDMB-CA series synthetic cannabinoids.

To address this challenge, researchers from the Xinjiang Technical Institute of Physics and Chemistry of the Chinese Academy of Sciences have developed an innovative zinc(II)-enhanced excimer fluorescence probe. Utilizing a conjugation modulation and metal-bridging strategy, the probe achieves highly specific recognition of MDMB-CA series synthetic cannabinoids through multiple non-covalent interactions.

Theoretical analysis revealed that the ratiometric fluorescence emission results from a transition from excimer emission to fluorescence resonance energy transfer (FRET)-based emission, elucidating the optical response mechanism.

The work is published in the journal Angewandte Chemie International Edition.

Experimental results demonstrate that the probe can specifically detect multiple MDMB-CA series synthetic cannabinoids within five seconds, with no interference from 14 potentially confounding substances. The team further developed a portable detection chip integrating extraction and enrichment functions, enabling accurate detection of synthetic cannabinoids in complex matrices such as e-cigarette oil and tobacco leaves. Additionally, the probe is capable of detecting synthetic cannabinoids and their metabolites in urine samples.

This study introduces a novel excimer fluorescence probe based on conjugation modulation and metal-bridging strategies, offering a new approach for the detection and identification of synthetic cannabinoids. Beyond advancing the field of synthetic cannabinoid detection, this research also contributes to the broader development of sensing probes and provides new insights for accurately detecting structurally diverse and weakly reactive chemical substances.

More information: Yihang Wang et al, Zinc(II)‐Enhanced Excimer Probe for Recognition of MDMB‐CA Synthetic Cannabinoids, Angewandte Chemie International Edition (2025). DOI: 10.1002/anie.202423576

Journal information: Angewandte Chemie International Edition 

Provided by Chinese Academy of Sciences