Category: Chemistry

A new paper published in Energy Material Advances explores Eu³⁺-Bi³⁺ codoping double perovskites for single-component white-light-emitting diodes.

“With lead-halide perovskites reaching a mature research stage approaching product marketing, concerns remain about the materials’ stability and the toxicity of lead-based salts,” said paper author Hongwei Song, professor at College of Electronic Science and Engineering, Jilin University.

Double perovskites with Cs₂AgInCl₆ composition, often doped with various elements, have been in the spotlight owing to their intriguing optical properties, namely, self-trapped exciton (STEs) emission and dopant-induced photoluminescence. This interest has sparked different synthesis approaches towards both crystals and nanocrystals, and the exploration of many alloy compositions with mono- and trivalent cations other than Ag⁺ and In³⁺.

Song explained that, in the development of lead-free perovskite materials, people’s first thought is to replace Pb element with a non-toxic element. In order to replace Pb in halide perovskite, researchers chose several low-toxic cations in the same period closest to it, such as Sn, Ge, Bi, Sb, In, etc., because they have a similar inactive shell s orbital.

This is the key to the unique photoelectric properties of perovskite materials. Lead-based perovskite materials have attracted great attentions in solid-state lighting area due to their high efficiency, high color rendering and tunable luminescence performance. This is both an opportunity and a challenge for the overall development of the photoelectric industry.

“Since the pioneering work on Cs₂AgInCl₆ in 2017 reported by Giustino et al. and Zhou et al. nearly simultaneously, many efforts have been devoted to its synthesis, modification of its composition, study of its electronic structure, optoelectronic properties, and applications. Recently, a record of white light emission with 86 % PLQY was achieved by Luo et al. via simultaneous alloying of Ag⁺ with Na⁺ and Bi³⁺ doping, marking an important milestone in the development of Cs₂AgInCl₆ related materials,” Song said.

“Despite several advantages, major issues with these lead halide perovskites remain their poor stability and toxicity. In order to solve such problems, various attempts have been made to reduce the toxicity of perovskites while still maintaining their efficient optical properties.”

The existence of Bi³⁺ ions decrease the excitation (absorption) energy, provides a new absorption channel and increases the energy transfer rate to Eu³⁺ ions. Through adjusting the Bi³⁺ and Eu³⁺ concentrations, a maximum photoluminescence efficiency (PLQY) of 80.1% is obtained in 6% Eu³⁺ and 0.5% Bi³⁺ co-doped Cs₂AgInCl₆ DPs.

“The energy transfer efficiency can be fitted with the decay rates under different Bi³⁺ doping concentrations. It can be seen that the energy transfer rate improves as a whole with the increase of the doping concentration of Bi³⁺, and the optimum energy transfer rate corresponding to the Bi³⁺ concentration is 0.5%. Next, we conducted PLQY test on the materials. For the undoped Cs₂AgInCl₆ DPs, PLQY is only 0.5%, which dramatically increases to 20.1% after the addition of Bi³⁺. After [being] co-doped with Eu³⁺ and Bi³⁺ ions, PLQY continues to increase, and reaches the maximum of 80.1% when the Eu concentration reaches 6%,” Song said.

“Here, we propose a possible mechanism to describe Eu³⁺ emission in Bi/Eu3+: Cs₂AgInCl₆. Cs₂AgInCl₆ DP is a direct bandgap semiconductor. Bi³⁺ doping provides a new absorption channel for the material, which may be caused by the contribution of the Bi³⁺ orbital in the band edge, breaking the STE-state compatibility ban transition, generating a new light absorption channel at a lower energy, and promoting the PLQY emitted by STE. For the Eu³⁺emission, we think there are two pathways. First, the energy transfer from STE to Eu³⁺ ions is possible as we have observed the Eu³⁺ emission in the Eu³⁺ doped Cs2AgInCl6 DPs. Second, the Eu3+ emission may mainly come from the energy transfer from Bi³⁺ ions to Eu³⁺ ions. The Bi³⁺ ions absorb the excitation light and transfer the energy from ¹P₁, ³P₂, ³P₁, ³P₀ levels of Bi³⁺ ions to ⁵D₃, ⁵D₂, ⁵D₁ and ⁵D₀ levels of Eu³⁺ ions. The characteristic emission of Eu³⁺ ions is then formed through ⁵D₀→⁷F_j(j=0,1,2,3) transitions.”

“Finally, we prepared the white light emitting diodes based on Bi³⁺ and Eu³⁺ codoped Cs₂AgInCl₆ DPs were fabricated with the optimum color rendering index of 89, the optimal luminous efficiency of 88.1 lm/W and a half-lifetime of 1493 h. This strategy of imparting optical functions to metal halide DPs may lead to future applications, such as optical fiber communications, daily lighting, military industry, displays, and other fields,” Song said.

More information: Tianyuan Wang et al, Eu³⁺-Bi³⁺ Codoping Double Perovskites for Single-Component White-Light-Emitting Diodes, Energy Material Advances (2023). DOI: 10.34133/energymatadv.0024

Provided by Beijing Institute of Technology Press Co., Ltd

Collagen is the protein that holds our body together. It is produced inside cells, from where it must be transported to its site of action in connective tissue. The protein domain that is responsible for the recognition of collagen has previously been mistaken for a subform of another.

Dr. Oliver Arnolds and Professor Raphael Stoll from the Faculty of Chemistry and Biochemistry at Ruhr University Bochum, Germany, have characterized and named this domain for the first time. They reported on the so-called MOTH domain of the TANGO1 protein family in the journal Nature Communications on April 20, 2023.

How collagen reaches its site of action

Almost all organisms that have more than one cell require collagen to hold their bodies together. In some mammals, it accounts for up to 30% of body weight. Collagen is a huge protein that is produced in the so-called endoplasmic reticulum, an organelle inside cells. It then has to be exported from the organelle and from the cell, because it is needed in the space between the cells in the connective tissue.

A family of proteins known as TANGO1 is responsible for identifying and transporting the collagen. Made up of more than 1,000 amino acids, these proteins are very large indeed. TANGO1 proteins sometimes spread across various cell organelles and the cytoplasm. When the TANGO1 protein detects a maturating collagen, it supports the formation of a tunnel-like lipid connection that transports the collagen from its place of manufacture to its site of action.

A distinct structure

In order to perform these mechanisms, TANGO1 has a specific domain, i.e., a functional area with a defined 3D structure. “Up to now, we have assumed that this domain is similar to the so-called SH3 structure and regarded it as a substructure,” says Raphael Stoll.

In the current study, however, he and Oliver Arnolds demonstrated by means of NMR spectroscopy that there are structural differences between the collagen-recognition domain of TANGO1 and the canonical SH3 domain. These differences are so significant in terms of biochemistry that they warrant referring to this TANGO1 domain as a separate structure. Hence, they named this collagen-recognizing domain MOTH. “The name is an acronym for the total of four proteins that adopt exactly this structure: MIA, Otoraplin, TALI/TANGO1 homology,” explains Raphael Stoll.

The discovery of the MOTH domain provides insights into evolution, because both vertebrates and invertebrates such as insects need collagen. “The MOTH domain is very old in evolutionary terms, approximately several hundred million years,” points out Raphael Stoll.

However, as invertebrates separated from vertebrates, the domain changed during evolution. “We assume that this process has coincided with the evolution of several different collagens. While insects have only one collagen, humans are found to have 28 different variations of it. These findings help improve our understanding of the collagen export process and could prove useful in future drug developments for fibrosis,” concludes Stoll.

More information: Oliver Arnolds et al, Characterization of a fold in TANGO1 evolved from SH3 domains for the export of bulky cargos, Nature Communications (2023). DOI: 10.1038/s41467-023-37705-4

Journal information: Nature Communications 

Provided by Ruhr-Universitaet-Bochum 

Chemical engineers at Monash University have developed an industrial process to produce acetic acid that uses the excess carbon dioxide (CO₂) in the atmosphere and has a potential to create negative carbon emissions.

Acetic acid is an important chemical used in several industrial processes and is an ingredient in household vinegar, vinyl paints and some glues. Worldwide industrial demand for acetic acid is estimated to be 6.5 million tons per year.

This world-first research, published in Nature Communications, shows that acetic acid can be made from captured CO₂ using an economical solid catalyst to replace the liquid rhodium or iridium based catalysts currently used.

Liquid catalysts require additional separation and purification processes. Using a solid catalyst made from a production method that doesn’t require further processing also reduces emissions.

Lead researcher Associate Professor Akshat Tanksale said the research could be a widely adopted practice for industry. “CO₂ is over abundant in the atmosphere, and the main cause of global warming and climate change. Even if we stopped all the industrial emissions today, we would continue to see negative impacts of global warming for at least a thousand years as nature slowly balances the excess CO₂,” Prof. Tanksale said.

“There is an urgent need to actively remove CO₂ from the atmosphere and convert it into products that do not release the captured CO₂ back into the atmosphere. Our team is focused on creating a novel industrially relevant method, which can be applied at the large scale required to encourage negative emissions.”

The research team first created a class of material called the metal organic framework (MOF) which is a highly crystalline substance made of repeating units of iron atoms connected with organic bridges.

They then heated the MOF in a controlled environment to break those bridges, allowing iron atoms to come together and form particles of a few nanometers in size.

These iron nanoparticles are embedded in a porous carbon layer, making them highly active while remaining stable in the harsh reaction conditions. This is the first time an iron based catalyst has been reported for making acetic acid.

From an industrial point of view, the new process will be more efficient and cost effective. From an environmental perspective, the research offers an opportunity to significantly improve current manufacturing processes that pollute the environment.

This means a solution to slow down or potentially reverse climate change while providing economic benefits to the industry from the sales of acetic acid products.

The researchers are currently in the process of developing the process for commercialization in collaboration with their industry partners as part of the Australian Research Council (ARC) Research Hub for Carbon Utilization and Recycling.

More information: Waqar Ahmad et al, Aqueous phase conversion of CO2 into acetic acid over thermally transformed MIL-88B catalyst, Nature Communications (2023). DOI: 10.1038/s41467-023-38506-5

Journal information: Nature Communications 

Provided by Monash University 

How short is one second? The duration of a second can be defined as one 86,400th of a 24-hour day. A bullet train traveling at 300 km per hour can cover a distance of 83 meters in one second. On average, an individual’s blink lasts for 0.3 seconds, allowing for three blinks to occur within one second. A joint team of researchers from POSTECH has proposed a synthesis method for fluorine-based compound via a rapid mixing reaction between a gaseous component and liquid that takes less than a single second.

The research team led by Professor Dong-Pyo Kim and Jeong-Un Joo (Department of Chemical Engineering at POSTECH), and Professor Heejin Kim and Hyune-Jea Lee (currently, a researcher at Samsung Advanced Institute of Technology) from the Department of Chemistry at Korea University has successfully developed a new method for synthesizing trifluoromethyl intermediate (-CF3) from fluoroform (CHF3).

It involves the use of a special reactor capable of achieving an ultra-fast mixing between gas and liquid. This method offers promising prospects for the synthesis of novel fluorine-based new drugs. The research was published in Nature Communications.

Fluorine is not found in its pure form naturally, but instead exists solely in the form of various chemical compounds. Sodium fluoride, a compound containing fluorine, is used as an ingredient in toothpaste due to its ability to coat teeth and prevent cavities.

Recent studies have highlighted the potential of synthetic drug molecules containing fluorine as they possess high permeability into cell membranes of diseased tissues and exhibit strong binding affinity against proteins. Consequently, there is growing interest in the development of drugs containing fluorine.

There are several approaches to synthesizing trifluoromethyl, but the most cost-effective method involves substituting a hydrogen atom from fluoroform, a simple precursor, with another element or functional group. However, gaseous fluoroform is volatile, which makes it difficult to mix with liquids and exhibits low reactivity. Moreover, it decomposes instantly, requiring the addition of a substance that can react with it. Unfortunately, this process can result in unintended chemical reactions that lead to a low yield of trifluoromethyl.

To address the challenge of synthesizing trifluoromethyl from fluoroform, the research team developed a novel gas-liquid reactor with a zigzag-shaped channel and highly permeable non-porous membranes sandwiched between upper and lower channels. This configuration allowed for the swirling and mixing of superbase, a liquid utilized for dehydrogenation, and gaseous fluoroform within the reactor.

By breaking fluoroform bubbles into smaller pieces to increase the contact area between gas and liquid, the team was able to effectively produce trifluoromethyl anion (CF₃^–). Unlike traditional approaches, they produced a fluoride intermediate effectively without requiring stabilizers or additives.

The research team synthesized a fluorine-based compound by immediately adding a compound that will react with the fluoride anion intermediate. The entire process, which involved the generation of a fluorine anion intermediate from fluoroform took place within a second. The team maximized the formation of a trifluoromethyl anion, which is known to be short-lived, and rapidly facilitated the subsequent reaction before the intermediate decomposed.

This method allowed for improved yield of fluoride-based compounds and introduced a robust technique for the synthesis of fluorine-based drugs.

The research findings have significant implications for industrial applications in the economically efficient synthesis of fluoride compounds, making them more practical as well contributing significantly to studies on several unstable intermediates.

More information: Hyune-Jea Lee et al, Ex-situ generation and synthetic utilization of bare trifluoromethyl anion in flow via rapid biphasic mixing, Nature Communications (2023). DOI: 10.1038/s41467-022-35611-9

Journal information: Nature Communications 

Provided by Pohang University of Science and Technology

Most states in the U.S. allow people to use cannabis for medical or recreational purposes. Yet all states want their roadways to be safe. A breathalyzer that can accurately identify people who recently smoked cannabis might help them keep impaired drivers off the road—if such a device existed.

But developing a breathalyzer for cannabis is far more difficult than for alcohol, which people exhale in large amounts when drinking. In contrast, the intoxicating component of cannabis, called THC, is thought to be carried inside aerosol particles that people exhale. The total volume of aerosols can be very small, making it difficult to accurately measure their THC content. Currently, there is no standard method for doing this.

Now, researchers at the National Institute of Standards and Technology (NIST) and the University of Colorado Boulder have conducted a study in which they collected breath samples from people both before and after they smoked high-THC cannabis, aka marijuana, and used laboratory instruments (not a handheld device) to measure the amount of THC in their breath.

The goal of this study, published in the Journal of Breath Research, was to begin developing a protocol that yields reproducible results—a necessary step toward a reliable, validated field-based method.

The samples collected before people smoked were important because THC can persist in the bodies of people who frequently use cannabis for a month or more, long after the effects of the drug have worn off.

“One key question that we cannot yet answer is whether breath measurements can be used to distinguish between a person who uses cannabis regularly but hasn’t done so lately, and someone who consumed an hour ago,” said NIST supervisory chemical engineer and study author Tara Lovestead. “Having a reproducible protocol for breath measurements will help us and other researchers answer that question.”

The breath samples were collected in a mobile lab—a comfortably appointed white van that would park conveniently outside participants’ homes. This mobile pharmacology lab was developed by researchers at University of Colorado Boulder, including Cinnamon Bidwell, an assistant professor of psychology and neuroscience and a co-author of the study.

In addition, all participants purchased and used a consistent kind of high-THC cannabis prepared by a licensed dispensary in Boulder, Colorado. This study design allowed the authors to conduct their research without handling high-THC cannabis or otherwise running afoul of federal laws.

At the appointed time, participants popped into the van, gave their pre-use breath sample and also provided a blood sample. They then went back into their residence, smoked cannabis according to their usual custom and returned immediately to the van to provide a second blood sample. Since THC concentrations in blood spike immediately after consuming the drug, researchers compared the before-and-after blood samples to confirm that the participants had in fact just used it. An hour later, the participants gave their second breath sample.

Participants provided breath samples by blowing into a tube containing an “impaction filter” that captured aerosols from their breath. Later in the lab, the researchers extracted the material caught in the filter and measured the concentration of THC and other cannabis compounds using liquid chromatography with tandem mass spectrometry, a laboratory technique that identifies compounds and measures their amount.

Because this was a protocol development study that involved only 18 participants, the results of the analysis do not carry statistical weight. However, they do highlight the need for further study.

“We expected to see higher THC concentrations in the breath samples collected an hour after people used,” Lovestead said. However, THC levels spanned a similar range across pre-use and post-use samples. “In many cases, we would not have been able to tell whether the person smoked within the last hour based on the concentration of THC in their breath.”

“A lot more research is needed to show that a cannabis breathalyzer can produce useful results,” said NIST materials research engineer and co-author Kavita Jeerage. “A breathalyzer test can have a huge impact on a person’s life, so people should have confidence that the results are accurate.”

More information: Kavita M Jeerage et al, THC in breath aerosols collected with an impaction filter device before and after legal-market product inhalation—a pilot study, Journal of Breath Research (2023). DOI: 10.1088/1752-7163/acd410

Journal information: Journal of Breath Research 

Provided by National Institute of Standards and Technology 

For pharmaceuticals, knowing the chemical composition is not enough—molecular geometry and crystal structure also play an important role in a drug’s activity. By using a method based on electron diffraction, it has now been possible for a research team to determine the structure of Levocetirizine, as reported in the journal Angewandte Chemie. The advantage of this technique is that, unlike for X-ray crystallography, nanoscale crystals are sufficient.

Despite being chemically identical, many pharmaceutical substances may adopt different crystal structures or form cocrystals with an additive. This can significantly influence the properties of a drug, such as bioavailability, solubility, stability, and tabletability. Structural determinations are correspondingly important in the development of advanced solid pharmaceuticals.

Today, the standard and routine method for determining the three-dimensional structures of crystalline molecules and biological macromolecules with atomic resolution is single-crystal X-ray diffraction structure analysis (SCXRD). The atoms within the crystal diffract the X-ray radiation, forming a diffraction pattern from which the positions of the individual atoms in the structure of the crystal can be calculated. This requires sufficiently large, well-diffracting single crystals.

However, many compounds are difficult or impossible to crystallize. An alternative method is powder X-ray diffraction (PXRD), which can analyze a sample in the form of a powder. However, the data analysis is not straightforward and if the sample is a mixture of several phases of the same or different compounds, it is very difficult and often ambiguous.

A more recent technique is 3D-electron diffraction/micro-crystal diffraction (3D ED/MicroED). Instead of X-rays, electron beams from an electron microscope are diffracted. Because the interaction of matter with electrons is significantly stronger than interactions with X-rays, sub-micro to nanometer-sized crystals produce diffraction patterns that can be evaluated and direct analysis of components in microcrystalline mixtures becomes possible.

A team led by Durga Prasad Karothu and Panče Naumov has used 3D ED/MicroED to determine the structure of Levocetirizine dihydrochloride. Levocetirizine is an over-the-counter oral antihistamine used to treat allergy symptoms such as hay fever and hives. Although it has been in broad use, its crystal structure has remained unknown because no crystals good enough for X-ray crystallographic analysis could be grown. Recently, the structure of this medication was studied using powder X-ray diffraction and computer calculations—but uncertainty and ambiguity remained.

The team at New York University Abu Dhabi (United Arab Emirates), Rigaku Europe SE (Neu-Isenburg, Germany), and New York University (New York, U.S.) worked with crystals obtained by grinding commercially available tablets. In addition to determining the drug’s crystal structure, they were able to use a special evaluation process (dynamical refinement) to unambiguously determine the absolute configuration (the exact spatial arrangement of all atoms within the molecule) of Levocetirizine.

More information: Durga Prasad Karothu et al, The Elusive Structure of Levocetirizine Dihydrochloride Determined by Electron Diffraction, Angewandte Chemie International Edition (2023). DOI: 10.1002/anie.202303761

Journal information: Angewandte Chemie International Edition  , Angewandte Chemie 

Provided by Wiley 

Approximately one in three ticks in Estonia and up to one in four in Tallinn carry bacteria that cause borreliosis. Scientists of TalTech are investigating whether medicinal plants growing in Estonia could be used to fight Lyme disease and destroy the bacteria causing it.

The arrival of warmer weather and more people spending time outdoors bring risks that should be addressed. A tick, likely to be carrying at least one pathogen, can attach itself to human skin in natural areas. The abundance of ticks in Estonia and the prevalence of tick-borne pathogens have increased significantly in the last decade.

The results of the recently published National Institute for Health Development project ‘Mail a Tick!’ show that, of the six main viruses/bacteria included in the study, at least one pathogen was detected in 62.3% of all ticks examined. The better-known tick-borne diseases include tick-borne encephalitis and borreliosis.

More and more causes of Lyme disease

It is possible to be vaccinated against encephalitis as a viral disease; moreover, immunity develops as a result of contracting the disease. There is no preventive treatment for Lyme disease. Once infected, there is no immunity and the consequences can be severe. Lyme disease is caused by a group of bacteria called Borrelia burgdorferi sensu lato, which enter human bloodstream through tick bites.

The first sign of infection is an enlarging reddish patch around the bite site, but this is absent in as many as a third of cases. According to scientific articles published in many scientific journals, such as Frontiers in Neurology, Pain, The Lancet, and Clinical Microbiology and Infection, symptoms in the later stages of the disease can include damage to joints, nervous system, skin, and heart.

According to the National Institute of Health, approximately 28% of Estonian ticks are carriers of B. burgdorferi and more than 2,500 people are infected with Lyme disease each year. A comparison of the latest data with the results of surveys conducted in 2006–2009 and 2012–2014 shows that the prevalence of Lyme disease in ticks has increased two or three times in some places across Estonia.

It is important to know that tick-borne diseases can also be contracted in the cities. The 2018 National Institute for Health Development survey of green areas in the capital city showed that an average 35% of ticks collected from urban areas carried at least one pathogen, with the prevalence of bacteria causing Lyme disease being as high as 25% of ticks in some places.

Innovative treatments are needed

Lyme disease is treated with antibiotics, which are generally effective in the acute stage of the disease. However, if the disease goes unnoticed and treatment is delayed, it can develop into a chronic condition.

Persistent symptoms are caused by the more resistant forms of B. burgdorferi bacteria, namely round body forms and biofilm, which are not as sensitive to antibiotics as the bacteria in their original form—corkscrew-shaped, or individual spirochetes.

Novel treatments are needed to fight resistant forms of bacteria. There are many examples in research literature of the efficacy of various plant-derived compounds or phytochemicals against Lyme disease.

The instrumental analysis research group of TalTech has been involved in the research of Estonian plants for a long time, and the main goal of the group in recent years has been identifying phytochemicals that are effective against B. burgdorferi and discovering new lead compounds suitable for the treatment of chronic Lyme disease.

Although many Estonian plants are known as medicinal herbs with antibacterial properties, the alleged beneficial properties are often unconfirmed by scientific methods. The chemical study of Estonian plants allows identifying specific plant compounds responsible for different therapeutic properties.

Which plants are studied by chemists?

The instrumental analysis research group is working on a wide range of plants growing in Estonia that are more or less known as medicinal plants. As a result of the research, an overview of the chemical composition and beneficial properties of many local plant extracts will be available. The first part of the plant research focuses on the chemical characterization of the studied species, the identification of the main groups of compounds present in them, and the antioxidant properties of plant extracts.

Antioxidant activity of an extract suggests its potential therapeutic uses both as an antibacterial agent and in the treatment of diseases associated with oxidative stress, such as cancers. With a suitable solvent and extraction protocol, it is possible to isolate compounds with antibacterial properties from plants, from which the researchers hope to identify the ones suitable for the treatment of Lyme disease.

A detailed summary of this work can be found in a recent article published in the special issue of Molecules, which describes the identification and characterization of phytochemicals found in various Galium species growing in Estonia.

Extracts of Galium verum, Galium aparine, and Galium mollugo were found to have significant antioxidant properties. The main compounds identified in the extracts belonged in the polyphenol and iridoid classes. Representatives of these classes of substances have shown a wide range of beneficial therapeutic properties in many previous scientific studies.

Polyphenols are known both for the prevention and treatment of diseases related to oxidative stress and iridoids for their anti-inflammatory properties and as inhibitors of bacterial, viral, and fungal growth. An extract made from Galium verum flowers was found to have the strongest antioxidant properties. In addition, volatile compounds in Estonian Galium species were identified, of which phytochemicals found in all three plant species have been previously confirmed as inhibitors of bacterial and fungal growth.

The beneficial properties of Dipsacus fullonum L. are confirmed

The research team has successfully confirmed the anti-Borrelia properties of another plant growing in Estonia, the Dipsakus fullonum L. The results of this research were published last year in a special issue of the journal Pharmaceuticals and were recognized for their importance in this field. Iridoid-glycoside fraction was isolated from the extract of the Dipsacus fullonum L. plant, which showed high activity against Borrelia and a low risk to mammalian cells.

As compounds with activity against Borrelia account for about 15% of the total extract, the leaves of Dipsacus fullonum L. are an excellent natural source for extracting novel lead compounds for the treatment of Lyme disease.

Plantagos and honey are also examined

Scientists of the instrumental analysis research group of TalTech Merike Vaher, Piret Saar-Reismaa, Pille-Riin Laanet, Piia Jõul, and Olga Bragina will continue their work on the chemical characterization of Estonian plants and the development of suitable extraction methods for compounds with therapeutic potential.

Among other things, the activity of various Plantagos and of various types of Estonian honeys and pollen against Borrelia is currently being investigated and ongoing trials have shown promising results in both cases. The researchers of TalTech hope that the results of the research could point to new treatment options for doctors and their patients, and pave the way for clinical trials to help people with chronic Lyme disease.

More information: Pille-Riin Laanet et al, Phytochemical Screening and Antioxidant Activity of Selected Estonian Galium Species, Molecules (2023). DOI: 10.3390/molecules28062867

Journal information: The Lancet  , Pain  , Frontiers in Neurology  , Development 

Provided by Estonian Research Council

Scientists have long been challenged by the complex process of drug discovery and development, with investments that often go unrewarded. However, with the advancement of experimental technology and computer hardware, artificial intelligence (AI) has emerged as a leading tool in analyzing abundant and high-dimensional data.

In a new academic paper published in the journal Engineering titled “Artificial Intelligence in Pharmaceutical Sciences,” researchers detail the advantages of AI technology in all aspects of new drug research and development (R&D).

AI is capable of discovering new drugs more efficiently and at a lower cost. Through the explosive growth of biomedical data, AI has led to a revolution in drug R&D, from target discovery to preclinical research, automated drug synthesis, and influences on the pharmaceutical market. In the review, the authors provide a brief overview of common AI models in the field of drug discovery, then summarize and discuss in depth their specific applications in various stages of drug R&D.

The paper concludes that AI is advantageous in all aspects of new drug R&D. It can be used in the discovery of drug targets, the design and development of new drugs, preclinical research, clinical trial design, and post-market surveillance to assist in the design of safe and effective drugs.

AI greatly reduces the cycle time and cost of drug R&D. While some limitations still remain in the AI-based drug R&D process, the authors believe that AI is an indispensable technology in the drug R&D process. In the future, AI technologies will change the R&D paradigm of pharmaceutical sciences, providing personalized medicine to patients.

The authors of the paper propose further research to inject new energy into this field and keep the momentum going. The emergence of AI is gradually helping scientists unravel the mystery of large and complex biological systems, making it a game-changer in the drug R&D process. As technology continues to advance, the potential of AI in the pharmaceutical industry is limitless.

More information: Mingkun Lu et al, Artificial Intelligence in Pharmaceutical Sciences, Engineering (2023). DOI: 10.1016/j.eng.2023.01.014

Provided by Engineering

A team of researchers at Duke University and their collaborators have uncovered the atomic mechanisms that make a class of compounds called argyrodites attractive candidates for both solid-state battery electrolytes and thermoelectric energy converters.

The discoveries—and the machine learning approach used to make them—could help usher in a new era of energy storage for applications such as household battery walls and fast-charging electric vehicles.

The results appeared online May 18 in the journal Nature Materials.

“This is a puzzle that has not been cracked before because of how big and complex each building block of the material is,” said Olivier Delaire, associate professor of mechanical engineering and materials science at Duke. “We’ve teased out the mechanisms at the atomic level that are causing this entire class of materials to be a hot topic in the field of solid-state battery innovation.”

As the world moves toward a future built on renewable energy, researchers must develop new technologies for storing and distributing energy to homes and electric vehicles. While the standard bearer to this point has been the lithium-ion battery containing liquid electrolytes, it is far from an ideal solution given its relatively low efficiency and the liquid electrolyte’s affinity for occasionally catching fire and exploding.

These limitations stem primarily from the chemically reactive liquid electrolytes inside Li-ion batteries that allow lithium ions to move relatively unencumbered between electrodes. While great for moving electric charges, the liquid component makes them sensitive to high temperatures that can cause degradation and, eventually, a runaway thermal catastrophe.

Many public and private research labs are spending a lot of time and money to develop alternative solid-state batteries out of a variety of materials. If engineered correctly, this approach offers a much safer and more stable device with a higher energy density—at least in theory.

While nobody has yet discovered a commercially viable approach to solid-state batteries, one of the leading contenders relies on a class of compounds called argyrodites, named after a silver containing mineral. These compounds are built from specific, stable crystalline frameworks made of two elements with a third free to move about the chemical structure. While some recipes such as silver, germanium and sulfur are naturally occurring, the general framework is flexible enough for researchers to create a wide array of combinations.

“Every electric vehicle manufacturer is trying to move to new solid-state battery designs, but none of them are disclosing which compositions they’re betting on,” Delaire said. “Winning that race would be a game changer because cars could charge faster, last longer and be safer all at once.”

In the new paper, Delaire and his colleagues look at one promising candidate made of silver, tin and selenium (Ag₈SnSe₆). Using a combination of neutrons and X-rays, the researchers bounced these extremely fast-moving particles off atoms within samples of Ag₈SnSe₆ to reveal its molecular behavior in real-time. Team member Mayanak Gupta, a former postdoc in Delaire’s lab who is now a researcher at the Bhabha Atomic Research Center in India, also developed a machine learning approach to make sense of the data and created a computational model to match the observations using first-principles quantum mechanical simulations.

The results showed that while the tin and selenium atoms created a relatively stable scaffolding, it was far from static. The crystalline structure constantly flexes to create windows and channels for the charged silver ions to move freely through the material. The system, Delaire said, is like the tin and selenium lattices remain solid while the silver is in an almost liquid-like state.

“It’s sort of like the silver atoms are marbles rattling around about the bottom of a very shallow well, moving about like the crystalline scaffold isn’t solid,” Delaire said. “That duality of a material living between both a liquid and solid state is what I found most surprising.”

The results and, perhaps more importantly, the approach combining advanced experimental spectroscopy with machine learning, should help researchers make faster progress toward replacing lithium-ion batteries in many crucial applications. According to Delaire, this study is just one of a suite of projects aimed at a variety of promising argyrodite compounds comprising different recipes. One combination that replaces the silver with lithium is of particular interest to the group, given its potential for EV batteries.

“Many of these materials offer very fast conduction for batteries while being good heat insulators for thermoelectric converters, so we’re systematically looking at the entire family of compounds,” Delaire said. “This study serves to benchmark our machine learning approach that has enabled tremendous advances in our ability to simulate these materials in only a couple of years. I believe this will allow us to quickly simulate new compounds virtually to find the best recipes these compounds have to offer.”

More information: Qingyong Ren et al, Extreme phonon anharmonicity underpins superionic diffusion and ultralow thermal conductivity in argyrodite Ag8SnSe6, Nature Materials (2023). DOI: 10.1038/s41563-023-01560-x

Journal information: Nature Materials 

Provided by Duke University