Tag: X-ray diffraction

X-raying auditory ossicles – a new technique reveals structures in record time

X-raying auditory ossicles – a new technique reveals structures in record time

Scientists at the Paul Scherrer Institute PSI have refined an X-ray diffraction technique for detecting biological structures from nanometres to millimetres – reducing the time needed to make the measurement from around one day to about an hour. This opens up a wide range of possibilities for biomedical research – from analysing bone and tissue structures to supporting the development of new implants.

Biological materials are masterpieces created by nature. Bones, for example, are extremely hard, yet at the same time elastic enough to withstand lateral forces without breaking easily. This combination of properties results from their hierarchical structure as composite materials – they combine materials that have different structures on different scales. Human-made composite materials are similar in the way they are made up. In reinforced concrete, for example, the concrete component, consisting of cement and sand, can withstand high pressure, while a steel mesh provides high tensile strength and transverse stability. 

Until now, examining such biological materials in detail has required the use of several different instruments, such as electron microscopes or classic light microscopes. However, scientists at the PSI Center for Photon Science have now refined an X-ray diffraction technique that was developed at the institute ten years ago, allowing it to be used to characterise materials on scales from nanometres to millimetres simultaneously and much faster than before. A complete scan now only takes about an hour, instead of a whole day.

To demonstrate the efficiency of their method, the researchers used the Swiss Light Source SLS to reveal the alignment of collagen fibres in a human ossicle known as the incus, or anvil. Collagen fibres are thread-like protein structures that provide tensile strength and elasticity to bones. “In doing so, we have taken the leap from a scientific method to a practical technique,” says Christian Appel, postdoctoral researcher and first author of the study. The results have now been published in the journal Small Methods as its cover story. In future, this method could be valuable in areas such as the study of complex tissue, the analysis of bone diseases and the optimisation of implant designs.

Read more on the PSI website

Image: Scientists at PSI were able to observe the local collagen structures in an ossicle by scanning it with an X-ray beam. The different colours of the cylinders indicate how strongly the collagen bundles are spatially aligned in a section measuring 20 by 20 by 20 micrometres.

Credit: © Paul Scherrer Institute PSI/Christian Appel

Is it light or humidity? Scientists identify the culprits of emerald green degradation in masterpieces

Is it light or humidity? Scientists identify the culprits of emerald green degradation in masterpieces

An international team of researchers have found what triggers degradation in one of the most popular pigments used by renowned 19th and 20th century painters. Using a multi-method approach, including advanced synchrotron radiation techniques, they’ve unveiled how light and humidity affect the masterpieces over time, and have proposed a strategy for its mitigation and monitoring. The results are out now in Science Advances.
During the 19th century, the Second Industrial Revolution sparked major advances in chemistry, giving rise to synthetic pigments that transformed art. Among them was emerald green, a vivid copper arsenite pigment admired for its brilliance and intensity.


Emerald green was used by well-known late 19th and early 20th century painters, such as Paul Cézanne, Claude Monet, Vincent van Gogh, Edvard Munch, and Robert Delaunay. Some of these painters, including Van Gogh, quickly realised that the paint would change over time, losing its original brilliant colour, cracking and triggering surface deformations. It was discovered later that it was also highly toxic.


Light and humidity


Researchers believe emerald green degrades because its chemical composition is highly unstable under light, humidity, and certain atmospheric gases. These conditions can cause the pigment to react and release arsenic compounds, alter its colour, or form dark copper oxides.
Now a research team led by the Institute of Chemical Sciences and Technologies “Giulio Natta” (SCITEC) of CNR and the Department of Chemistry, Biology and Biotechnology of the University of Perugia, in collaboration with the ESRF, the European Synchrotron, and the University of Antwerp, has investigated what triggers the degradation of emerald green. The study1 aims to improve strategies for preserving the masterpieces containing this pigment and to develop new methods to monitor their conservation state. “It was already known that emerald green decays over time, but we wanted to understand exactly the role of light and humidity in this degradation”, explains Letizia Monico, senior researcher at the SCITEC-CNR, corresponding and first author of the publication, together with Sara Carboni Marri, a former PhD student from the same research group.

Read more on the ESRF website

Image:  Photograph of The Intrigue (1890, Royal Museum of Fine Arts Antwerp, KMSKA) by James Ensor

Credit: Royal Museum of Fine Arts Antwerp, KMSKA

Synchrotron light reveals the previously unknown crystal structure of dypingite

Synchrotron light reveals the previously unknown crystal structure of dypingite

A team of researchers from the University of Oslo and the ALBA Synchrotron has determined for the first time the crystal structure of dypingite, a naturally occurring hydrated magnesium carbonate mineral. Using synchrotron X-ray diffraction at ALBA, the scientists revealed how humidity triggers subtle but reversible disorder in the mineral’s structure. These findings, published in the Journal of Applied Crystallography, help explain the elusive nature of dypingite’s atomic arrangement and could improve our understanding of carbon mineralization – a natural process with implications for carbon dioxide capture and storage.

Understanding the structure of crystals and their defects has led to a number of surprising innovations across various fields, from modern electronics and computing to high-precision MRI machines and large high-energy accelerators. In light of this, researchers have been studying a number of disordered solid materials and exploring methods to engineer disorder within their crystal structures to gain control over the physical and chemical properties of the compounds. One mineral of growing interest is dypingite, a naturally-occurring hydrated magnesium carbonate mineral that forms through the reaction of magnesium-rich rocks with carbon dioxide and water.

These minerals have been found to play a role in natural carbon sequestration, whereby they lock atmospheric carbon dioxide into stable solid forms over geological timescales. Furthermore, dypingite forms flower-like nanoparticles that could have applications in catalysis and water filtration. Identifying their crystal structure could enable scientists to exploit these properties. Dypingite was first described in the 70’s. However, until now, it has been notoriously difficult to characterize due to its complex layering and sensitivity to moisture.

Read more on the ALBA website

Image: Naturally formed dypingite: (left) microphotograph of a dypingite layer on a serpentine rock; (right) SEM image of dypingite’s layers

X-Rays Shed Light on Possible New Treatments for TB

X-Rays Shed Light on Possible New Treatments for TB

SCIENTIFIC ACHIEVEMENT

X-ray diffraction data, collected at the Advanced Light Source (ALS) and other Department of Energy light sources, revealed the crystal structure of CMX410, a new compound that targets a key enzyme (Pks13) in the cell membrane of the bacterium responsible for tuberculosis (TB).

SIGNIFICANCE AND IMPACT

CMX410 is a promising new candidate to treat TB, including multidrug-resistant strains.

New treatments needed to tackle an old foe

TB is a deadly infectious disease caused by the bacterium Mycobacterium tuberculosis (Mtb). According to the World Health Organization, an estimated 10.8 million people contracted TB globally in 2023, and 1.25 million died from the disease. While antibiotics are effective for drug-sensitive TB cases, multidrug-resistant Mtb strains can evade common drug therapies.

Drug-resistant cases require a regimen that is often more expensive, toxic, and time-intensive. Patients are required to take six or more medications daily for up to 20 months. New approaches are urgently needed to shorten the course of drug interventions and address widespread multidrug-resistant strains.

A multi-institutional study led by researchers at Texas A&M University and the Calibr-Skaggs Institute for Innovative Medicine sought to find new treatments to address multidrug-resistant TB. The team screened a library of 406 compounds that belong to an active class of molecules [i.e., sulfur fluoride exchange (SuFEx)] to evaluate their efficacy against Mtb. The team developed one promising compound into CMX410, which targets Pks13, an enzyme essential for microbial cell wall biosynthesis.

Read more on the ALS website

Image: A cross-section of the crystal structure for the enzyme Pks13 (the surface colored pink and blue by hydrophobicity) as it interacts with CMX410 (shown as stick-like structure), a new drug candidate for TB

Credit: ALS

Robust supercrystals for the LEDs of the future

Robust supercrystals for the LEDs of the future

Nanometre-sized crystals of perovskite offer great potential for applications in the field of light-emitting diodes, solar cells and optical switching elements. A particularly interesting arrangement occurs when a large number of these nanocrystals join to form a larger structure – a supercrystal. Researchers at the University of Tübingen have now found a novel way of achieving this. They resorted to a clever technique to produce perovskite supercrystals that are particularly stable and therefore useful. Some important analyses were carried out at DESY: Using its X-ray source PETRA III, the team managed to determine the precise structure of the supercrystals. They are now presenting their findings in the journal ACS Nano.

Perovskites, named after the Russian mineralogist Lev Perovski, are a class of crystalline materials with a characteristic lattice structure. Lead halide perovskites are particularly promising, as they can be produced relatively easily by chemical methods and have remarkable optoelectronic properties – which is why these materials are the subject of intensive research. The first practical applications now appear to be within reach: Experts are working on high-performance solar cells based on perovskites, as well as on a new generation of highly efficient LEDs and laser chips.

Perovskite nanocrystals are a particularly exciting area of research. “Their optoelectronic properties depend heavily on their size – which is typical of quantum behaviour,” explains Jonas Hiller from the University of Tübingen, one of the authors of the study. “Because of this, their properties can be specifically customised. The energy of the light they absorb or emit varies depending on their composition and their size.”

Under certain conditions, these perovskite nanocrystals can form larger structures, creating a supercrystal. “This is a crystal made up of crystals,” Hiller explains. “You can compare it to a Rubik’s Cube which is made up of several smaller cubes.” The exciting thing is that while the individual nanocrystals retain their desired quantum properties, they can be handled as a macroscopic unit and thus deployed in practical applications.

Forming a supercrystal in two phases

Until now, supercrystals like this have been created by allowing a solvent containing the perovskite to slowly evaporate. The resulting structures form very gradually on the substrate. “However, the supercrystals are produced at random sites around the substrate,” explains the project manager Ivan Zaluzhnyy from Tübingen. “Also, the individual nanocrystals are surrounded by a protective layer of organic molecules which makes the entire supercrystal very soft.” As a result, they break very easily when you try to move them around mechanically. This poses a real obstacle for applications in which the positioning of the materials is crucial, such as between two electrodes in an electrical component.

To solve this problem, the team opted for an alternative approach: two-phase diffusion. A solution containing the nanocrystals is layered on top of a second liquid: acetonitrile. This acts as an anti-solvent for the perovskite crystals. As it slowly penetrates the solution containing the nanocrystals, it gradually reduces their solubility. “This results in crystal growth beginning at the boundary surface between the two phases,” explains Jonas Hiller. The acetonitrile displaces the organic molecules coating the crystals, resulting in a firmer, more stable structure.

In order to examine the structure of these supercrystals more closely, the team used the narrow X-ray beam at GINIX, an instrument installed at the PETRA III beamline P10. “The beam diameter of just 300 nanometres makes it possible to examine different regions within a supercrystal with high precision,” explains DESY physicist Wojciech Roseker. And Jonas Hiller adds: “The extremely high quality of the diffraction data was a key element of this study. It enabled us to analyse the structure of the supercrystals in great detail.”

The team found that the supercrystals produced, typically had an area of 10 by 10 square micrometres but were significantly thicker than the comparatively flat structures that could be achieved using the old method. Their height was more than five micrometres which improves their stability. This makes the supercrystals robust enough to be gripped with micromanipulators and moved to other locations – a first for perovskite structures.

Read more on DESY website

Image: Like a crystal rubik’s cube: The research team has found a way to create ordered perovskite supercrystals.

Credit: University of Tübingen, figure from original publication

Structure of liquid carbon measured for the first time

Structure of liquid carbon measured for the first time

With the declared aim of measuring matter under extreme pressure, an international research collaboration headed by the University of Rostock and the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) used the high-performance laser DIPOLE 100-X at European XFEL for the first time in 2023. With spectacular results: In this initial experiment they managed to study liquid carbon – an unprecedented achievement, as the researchers report in the journal Nature (DOI: 10.1038/s41586-025-09035-6). 

Liquid carbon can be found, for example, in the interior of planets and plays an important role in future technologies like nuclear fusion. To date, however, only very little was known about carbon in its liquid form because in this state it was practically impossible to study in the lab: Under normal pressure carbon does not melt but immediately changes into a gaseous state. Only under extreme pressure and at temperatures of approximately 4,500 degrees Celsius – the highest melting point of any material – does carbon become liquid. No container would withstand that.

Laser compression, on the other hand, can turn solid carbon into liquid for fractions of a second. And the challenge was to use these fractions of a second to take measurements. In a previously unimaginable way, this has now become reality at the European XFEL, the world’s largest X-ray laser with its ultrashort pulses, in Schenefeld, near Hamburg.

Unique measuring technology in this combination

The unique combination of the European XFEL with the high-performance laser DIPOLE100-X was crucial for the success of the experiment. It was developed by the British Science and Technology Facilities Council and made available to scientists from all over the world by the HIBEF User Consortium (Helmholtz International Beamline for Extreme Fields). A community of leading international research institutions at the HED-HIBEF (High Energy Density) experimental station at European XFEL has now combined powerful laser compression with ultrafast X-ray analysis and large-area X-ray detectors for the first time.

In the experiment, the high-energy pulses of the DIPOLE100-X laser drive compression waves through a solid carbon sample and liquefy the material for nanoseconds, that is, for a billionth of a second. During this nanosecond, the sample is irradiated with the ultrashort X-ray laser flash of the European XFEL. The carbon atoms scatter the X-ray light – similar to the way light is diffracted by a grating. The diffraction pattern allows inferences to be drawn about the current arrangement of the atoms in the liquid carbon.

The whole experiment only lasts a few seconds but is repeated many times: every time with a slightly delayed X-ray pulse or under slightly different pressure and temperature conditions. Many snapshots combine to make a movie. Researchers have thus been able to trace the transition from solid to liquid phase one step at a time.

Read more on European XFEL website

Image: Groundbreaking experiment at European XFEL: Research team measured structure of liquid carbon for the first time

Credit: Martin Kuensting / HZDR

Watching superheated silver nanoparticles bubbling

Watching superheated silver nanoparticles bubbling

Matter under extreme conditions, especially at extreme temperatures and pressures, plays an important role in many fields. These range from astrophysics and geology over inertial fusion reactor studies to applied research on material processing by laser ablation. Due to the complex behaviour of matter under such conditions the underlying interactions are not yet fully understood. In recent years isolated nanoparticles, which form well-defined crystalline structures at lower temperatures, have proven to be suitable test objects for the study of such questions.

A team of researchers including DESY scientists around Daniela Rupp (ETH Zurich), Thomas Möller (TU Berlin) and Bernd v. Issendorff (Univ. Freiburg), as well as several groups from Univ. Rostock (Ingo Barke, Karl-Heinz Meiwes-Broer, Thomas Fennel), has applied time-resolved soft X-ray diffraction at the CAMP endstation at FLASH to study the dynamics of superheated silver nanoparticles in a laser pump – FEL probe experiment. They observed that silver nanoparticles, when strongly laser-heated via their plasmon resonance, exhibit a wide range of phenomena, from melting over cavitation-induced bubble-like expansion to explosion, as a function of the excitation strength. “Depending on the heating conditions and the temporal evolution, we could identify different classes of diffraction images, stemming from faceted, round, hollow, fragmenting or sometimes finally exploding nanoparticles”, Alessandro Colombo (ETH Zurich), one of the three first authors, explains.

Read more on DESY website

Image: Diffraction image of a hollow silver nanoparticle (left) measured at FLASH, along with its reconstruction (top right) and a corresponding picture from MD simulations (bottom right).

Credit: T. Reichenbach, Univ. Freiburg

Towards prevention of diabetes linked substance produced by human gut microbiota 

Towards prevention of diabetes linked substance produced by human gut microbiota 

The team at the Novo Nordisk Foundation funded life science beamline MicroMAX welcomed the first users in December 2023. In the experiment the users investigated an enzyme that may be found in some bacteria of human gut microbiota and may have a role in the development of diabetes and other diseases.

An enzyme called urocanate reductase may be present in the bacteria that are found in the human gut. The enzyme breaks down urocanic acid, a natural constituent of skin and other tissues of the body, into the metabolite imidazole propionate. The metabolite has been linked to diabetes and other diseases.

The user team from Lund University used MicroMAX to investigate the molecular structure of the enzyme.

“A possible therapeutic strategy is to inhibit the enzyme and prevent the imidazole propionate production. The high-resolution atomic structure is needed to design inhibitor molecules that could occupy the active site of the enzyme,” says Raminta Venskutonyte, one of the researchers who conducted the study.

The experiment was conducted using X-ray diffraction at room temperature on a crystal prepared from a purified enzyme. One of the features of MicroMAX is that the experimental setup can handle even small amounts of samples, so-called microcrystals. It is important as it lets the researchers study samples that cannot be made to form large crystals and extend investigations into new areas.

“We aim to carry out time-resolved studies using microcrystals of urocanate reductase to further clarify its enzymatic mechanism. We are also looking forward to using MicroMAX in other projects involving medically interesting proteins, which only yield microcrystals,” concludes Raminta Venskutonyte.

Read more om the MAX IV website

Image: Raminta Venskutonyte in the experiment hutch at beamline MicroMAX

Deciphering the sugar transport in plants

Deciphering the sugar transport in plants

Synchrotron studies to understand sucrose highway

In most plant species, sucrose is the main form of assimilated carbon produced during photosynthesis. Sucrose is essential for plant growth, as it provides a source of carbon to produce new molecules, but also energy for the plant cells. Sucrose has also an associated role as a signalling molecule, by regulating the growth of new organs, accumulation of storage proteins, and flowering in plants. Long-distance sucrose distribution from the green source tissues, generally leaves, to energy-demanding sink tissues (flowers, fruits, new organ in formation) is mediated by a specific and highly modified vascular tissue called phloem. The transport of sucrose in the phloem is an active transport, as sucrose is loaded in the conductive tissue by specific proteins from the SUC/SUT family. The SUC1 transporter from A. thaliana is located on the membrane of cells and use the proto-motive force to drive the loading of sucrose. Despite their key role in plants, the working mechanism of these SUCs transporters is not yet well understood.

A team of researchers from the Aarhus University recently published a new study in Nature Plants to understand the precise mechanism of action of the SUC1 transporter. They used X-ray diffraction data collected at I04 and I24 beamlines at Diamond to determine the 3D structure of this transmembrane protein. They wanted to understand how SUCs protein recognise sucrose, and how transport is proton coupled. As sugar transport is a key feature in plants, understanding how proteins can fine-tune the sugar concentration in conductive tissue is fundamental. Lead author of this study, Dr Bjørn Panyella Pedersen explained:

Active sucrose transport and loading into the phloem determines the turgor pressure. This pressure creates the vascular flow of nutrients (sucrose and all other components of the sap), and determines which parts of the plant will grow in response to environmental signals. Ultimately, we hope our research will help to augment control of growth and morphology in plants.

For their study, the team used a well-known plant model, Arabidopsis thaliana. This plant is widely used as model because it has a sequenced and annotated genome, and huge collections of mutant lines exists, allowing characterisation of plants where a specific gene is not expressed. Furthermore, this plant has a fast life cycle and produces numerous seeds.

In this study, the researchers present the structure of SUC1, and key elements to explain both the recognition of sucrose by the transporter, and the active transport by proton coupling. They produced SUC1 transporters and performed in-vivo assays to determine if the protein was functioning, and then proceed to solving the structure at the microfocus beamline I24. Dr Bjørn Panyella Pedersen says:

We have used Diamond’s beamlines I24 and I04 for our research since 2014, both in person and by remote data collection. We have always been very happy with the support and quality of the beamlines at Diamond. Brexit and the Corona years have made our access to the facility more challenging at times but with the help from the support staff we have been able to maintain our work at Diamond.

Read more on the Diamond website

Image: The 2.7 Å electron density map of SUC1 (2mFo-DFc map contoured at 1σ). Density corresponding to the N and C domain are coloured cyan and orange, respectively. EHR and IHR domains are coloured pale yellow. 

X-ray diffraction reveals ancient Egyptian illustration methods

X-ray diffraction reveals ancient Egyptian illustration methods

The ancient Egyptians used papyrus as a medium for communication and illustration, with the first illustrations appearing in the fifth and sixth dynasties (2500 – 2100 B.C.). Funerary documents, such as the Book of the Dead, flourished during the New Kingdom period as they were considered essential for entering the afterlife.

The Champollion Museum in Vif, France, holds a collection of 280 papyrus fragments, many of which show scenes from the Book of the Dead. The colours used in these illustrations are typical of the Egyptian palette and include blue, green, red, pink, yellow and white, with different characters and elements of the illustrations outlined with a black line.

Researchers from the ESRF and the Néel Institute CNRS/UGA in Grenoble, France, with collaborators from the Champollion Museum, worked together to gain a deeper understanding of the illustration processs used in ancient Egypt. A combination of optical microscopy, synchrotron X-ray powder diffraction, X-ray fluorescence and Raman spectroscopy was used to identify the pigments and their overall distribution.

Two of the papyrus fragments of the collection (PAP-6 and PAP-12) were examined on beamline ID22, where X-ray fluorescence and X-ray diffraction experiments were carried out. Mixed Rietveld and Pawley refinement was carried out against the XRD data to quantify the fine fraction and to consider the heterogeneous microstructure of the pigments.

Read more on the ESRF website 

High pressure synthesis in gallium sulphide chalcogenide

High pressure synthesis in gallium sulphide chalcogenide

Researchers from Universitat Politècnica de València, Universidad de La Laguna, Universidad de Cantabria and the ALBA Synchrotron have published a new work on high pressure chemistry in gallium (III) sulphide chalcogenide. In this work, relevant fingerprints (vibrational and structural) of a pressure-induced paralectric to ferroelectric phase transition are shown. This is the first time when a tetradymite-like (R3m) phase has been synthesized and observed experimentally in gallium-based sequichalcogenides. High pressure X-ray diffraction measurements were carried out at MSPD beamline of ALBA.

Gallium (III) sulphide (Ga2S3) is a compound of sulphur and gallium, that is a semiconductor that has a wide variety of applications in electronics and photonics: nano optoelectronics, photonic chips, electro-catalysis, energy conversion and storage, solar energy devices, gas sensors, laser-radiation detection, second harmonic generation, phase change memories or photocatalytic water splitting systems.

In this work published in Chemistry of Materials,scientists have shown relevant vibrational and structural fingerprints of a pressure-induced paraelectric to ferroelectric R-3m-to-R3m (β’-to-φ) phase transition under decompression on Ga2S3 chalcogenide.

This transition was theoretically predicted in several III−VI B2X3 compounds at high temperature (where B can be aluminium, gallium or indium and X, sulphur, selenium or tellurium). The novelty of this research stems from the synthesis of both phases: β-(R-3m) and α-In2Se3 (R3m)-like structures on Ga2S3 and tuning them via decreasing pressure. Within the III−VI B2X3 compounds, this R-3m-to-R3m (β’-to-φ-Ga2S3) phase transition had been observed experimentally only in the indium (III) selenide (In2Se3)compound, under varying temperature or pressure, to date.

This finding leads the way for designing cheap, nontoxic, nonrare-earth, and abundant element-based devices for second harmonic generation, photocatalytic splitting, ferroelectric, pyroelectric, and piezoelectric applications based on Ga2S3.

Read more on the ALBA website

Image: Samuel Gallego and Catalin Popescu at the MSPD beamline of ALBA.

Discovered: An easier way to create “Flexible Diamonds”

Discovered: An easier way to create “Flexible Diamonds”

As hard as diamond and as flexible as plastic, highly sought-after diamond nanothreads would be poised to revolutionize our world—if they weren’t so difficult to make. A team of scientists led by Samuel Dunning and Timothy Strobel of the Carnegie Institution for Science using high-brightness x-rays from the U.S. Department of Energy’s (DOE’s) Advanced Photon Source developed an original technique that predicts and guides the ordered creation of strong, yet flexible, diamond nanothreads, surmounting several existing challenges.  The innovation will make it easier for scientists to synthesize the nanothreads—an important step toward applying the material to practical problems in the future. The work was published in the Journal of the American Chemical Society.

Diamond nanothreads are ultra-thin, one-dimensional carbon chains, tens of thousands of times thinner than a human hair. They are often created by compressing smaller carbon-based rings together to form the same type of bond that makes diamonds the hardest mineral on our planet. However, instead of the three-dimensional carbon lattice found in a normal diamond, the edges of these threads are “capped” with carbon-hydrogen bonds, which make the whole structure flexible.

Dunning explains: “Because the nanothreads only have these bonds in one direction, they can bend and flex in ways that normal diamonds can’t.”

Scientists predict that the unique properties of carbon nanothreads will have a range of useful applications from providing sci-fi-like scaffolding on space elevators to creating ultra-strong fabrics. However, scientists have had a hard time creating enough nanothread material to actually test their proposed superpowers.

Read more on the APS website

Image: The starting sample of pyridazine—a six atom ring made up of four carbons and two nitrogens—changes under pressure as diamond nanothread formation progresses. The first and last images show that there has been a permanent color change between the samples after thread formation. The images don’t show individual threads, but “bulk” samples of pyridazine during compression, each around 40 microns thick with a 180-micron diameter.

Credit: Samuel Dunning

Unveiling the secrets of biofilms

Unveiling the secrets of biofilms

Most bacteria have the ability to form communities, biofilms, that adhere to a wide variety of surfaces and are difficult to remove. This can lead to major problems, for example in hospitals or in the food industry. Now, an international team led by Hebrew University, Jerusalem, and the Technical University Dresden, has studied a model system for biofilms at the synchrotron radiation facilities BESSY II at HZB and the ESRF and found out what role the structures within the biofilm play in the distribution of nutrients and water.

Bacterial biofilms can thrive on almost all types of surfaces: We find them on rocks and plants, on teeth and mucous membranes, but also on contact lenses, medical implants or catheters, in the hoses of the dairy industry or drinking water pipes, where they can pose a serious threat to human health. Some biofilms are also useful, for example, in the production of cheese, where specific types of biofilms not only produce the many tiny holes, but also provide its delicious taste.

Tissue with special structures

“Biofilms are not just a collection of very many bacteria, but a tissue with special structures,” explains Prof. Liraz Chai from the Hebrew University in Jerusalem. Together, the bacteria form a protective layer of carbohydrates and proteins, the so-called extracellular matrix. This matrix protects the from disinfectants, UV radiation or desiccation and ensures that biofilms are really difficult to remove mechanically or eradicate chemically. However, the matrix is not a homogeneous sludge: “It’s a bit like in a leaf of plants, there are specialized structures, for example water channels residing in tiny wrinkles,” says Chai. But what role these structures play and what happens at the molecular level in a biofilm was not known until now. Together with Prof. Yael Politi, TU Dresden, an expert in the characterization of biological materials, Chai therefore applied for measurement time at the synchrotron radiation source BESSY II at HZB.

“The good thing about BESSY II is that we can map quite large areas. By combining X-ray diffraction with fluorescence, not only can we analyze the molecular structures across the biofilm very precisely, but we can also simultaneously track the accumulation of certain metal ions that are transported in the biofilm and learn about some of their biological roles” Yael Politi points out.

Read more on the HZB website

Image: When bacteria join together to form communities, they may build complex structures. The photo shows wild-type Bacillus subtilis biofilms.

Credit: © Liraz Chai/HUJI

Probing the Structure of a Promising NASICON Material

Probing the Structure of a Promising NASICON Material

As physicists, materials scientists, and engineers continue striving to enhance and improve batteries and other energy storage technologies, a key focus is on finding or designing new ways to make electrodes and electrolytes.  One promising avenue of research involves solid-state materials, making possible batteries free of liquid electrolytes, which can pose fire and corrosion hazards.  An international group of researchers joined with scientists at Argonne National Laboratory to investigate the structure of crystalline and amorphous compounds based on the NASICON system, or sodium super-ion conductors. The work (using research carried out at the U.S. Department of Energy’s Advanced Photon Source [APS] and published in the Journal of Chemical Physics) reveals some substantial differences between the crystalline and glass phases of the NAGP system, which affect the ionic conductivity of the various materials.  The investigators note that the fraction of non-bridging oxygen (NBO) atoms appears to play a significant role, possibly altering the Na+ ion mobility, and suggest this as an area of further study.  The work provides fresh insights into the process of homogeneous nucleation and identifying superstructural units in glass ― a necessary step in engineering effective solid-state electrolytes with enhanced ionic conductivity. 

Because of their high ionic conductivity, materials with a NASICON structure are prime candidates for a solid electrolyte in sodium-ion batteries.  They can be prepared by a glass-ceramic route, which involves the crystallization of a precursor glass, giving them the usefulness of moldable bulk materials.  In this work, the research team specifically studied the NAGP system [Na1+xAlxGe2-x(PO4)3] with x = 0, 0.4 and 0.8 in both crystalline and glassy forms. Working at several different facilities, they used a combination of techniques, including neutron and x-ray diffraction, along with 27Al and 31P magic angle spinning and 31P/23Na double-resonance nuclear magnetic resonance spectroscopy.  The glassy form of NAGP materials was examined both in its as-prepared state and after thermal annealing, so that the changes on crystal nucleation could be studied.

Neutron powder diffraction measurements were performed at the BER II reactor source, Helmholtz-Zentrum Berlin, using the fine resolution powder diffractometer E9 (FIREPOD), followed by Rietveld analysis.  Further neutron diffraction observations were conducted at the Institut Laue-Langevin using the D4c diffractometer and at the ISIS pulsed neutron source using the GEM diffractometer.  X-ray diffraction studies were performed at X-ray Science Division Magnetic Materials Group’s beamline 6-ID-D of the APS, an Office of Science user facility at Argonne National Laboratory. 

Read more on the APS website

Image: Fig. 1. NASICON crystal structure showing the tetrahedral P(4) phosphate motifs (purple), octahedral GeO6 motifs (cyan) and Na+ ions (green). Oxygen atoms are depicted in red.

Analysing asteroid Ryugu samples

Analysing asteroid Ryugu samples

The asteroid Ryugu samples brought back by JAXA’s asteroid explorer “Hayabusa2” in December 2020 are analyzed by six initial analysis teams for one year from June 2021. Among the initial analysis teams, the “Stone Material Analysis Team” and the “Organic Macromolecule Analysis Team” conducts their analysis at the Photon Factory, KEK.

It is thought that asteroids such as Ryugu may have brought water and organic matter to the Earth in the past. By integrating the results of each team’s analysis, we will be closer to solving the great mystery of how life came to be on the Earth.

Read more on the HAYABUSA2-IMSS website

Image : Primordial solar system. 

AI Agent Helps Identify Material Properties Faster

AI Agent Helps Identify Material Properties Faster

High-throughput X-ray diffraction measurements generate huge amounts of data. The agent renders them usable more quickly.

Artificial intelligence (AI) can analyse large amounts of data, such as those generated when analysing the properties of potential new materials, faster than humans. However, such systems often tend to make definitive decisions even in the face of uncertainty; they overestimate themselves. An international research team has stopped AI from doing this: the researchers have refined an algorithm so that it works together with humans and supports decision-making processes. As a result, promising new materials can be identified more quickly.

A team headed by Dr. Phillip M. Maffettone (currently at National Synchrotron Light Source II in Upton, USA) and Professor Andrew Cooper from the Department of Chemistry and Materials Innovation Factory at the University of Liverpool joined forces with the Bochum-based group headed by Lars Banko and Professor Alfred Ludwig from the Chair of Materials Discovery and Interfaces and Yury Lysogorskiy from the Interdisciplinary Centre for Advanced Materials Simulation. The international team published their report in the journal Nature Computational Science from 19 April 2021.

Read more on the BNL website

Image: Daniel Olds (left) and Phillip M. Maffettone working at the beamline.

Credit: BNL