Artificial double-helix for geometrical control of magnetic chirality

A study published in ACS Nano demonstrated the imprinting of complex 3D chirality at the nanoscale using state-of-the-art fabrication techniques and magnetic microscopy at MISTRAL beamline of the ALBA Synchrotron. The results prove the possible control of the magnetic configuration with geometrical morphologies displaying 3D chirality and open a new avenue on applied nanomagnetism. The research was the result of a multiple collaboration of scientists from Cambridge, Glasgow and Zaragoza Universities, the ALBA Synchrotron and the Lawrence Berkeley Laboratory.

An object is chiral if its image in a mirror cannot bring to coincide with itself as our right and left hands. Chirality plays a major role in nature, for example DNA double helix is a chiral right-handed structure. In magnetism, interactions between spins which are sensitive to chirality generate, in 2D structures with engineered interfaces, complex magnetic configurations as skyrmions that may be of future use in spintronics. In this study, researchers demonstrate the imprinting of complex 3D chirality at the nanoscale using state-of-the-art fabrication techniques and magnetic microscopy at MISTRAL. By fabricating a double helix ferromagnetic structure, magnetic domains were created having the same chirality of the double helix. Moreover, if the geometrical chirality was inverted in the course of the fabrication of the strand, then, the chirality of the magnetic domains was also inverted. At the location were both magnetic chiralities meet, a confined 3D magnetization was evidenced. The ability to create chiral 3D structures with nano patterning enables the control of complex topological magnetic states that might be important for future materials in which chirality provides a specific functionality.

Read more on the ALBA website

Image: Figure: a) 3D-printing of a cobalt nano-helix by FEBID. After injection of Co2(CO)8 into the chamber of a scanning electron microscope (SEM) using a gas injection system (GIS), the focused electron beam (in green and magenta) alternatively exposes the two helix strands. b) Coloured SEM image of the nanostructure under investigation, consisting of two double-helices of opposite chirality joined at the tendril perversion marked *. Scale bar 250nm, c) XMCD image of the double helix studied, which changes geometric chirality at *. Image at zero field, after application of a saturating field H along the axis as indicated. D) XMCD image of the double-helix under study in the as-grown state. Scale bars in c) and d) 200 nm.

Understanding how the taxanes antitumoral drugs modulate cell microtubules

Researchers have found that addition of paclitaxel (a type of antitumoral drug) to microtubules alters their structure. This compound modulates the material properties of microtubules by converting destabilized growing microtubule ends into regions resistant to depolymerisation, eventually leading to cell death. Results were obtained at the NCD beamline of the ALBA Synchrotron.

Paclitaxel, one of the most commonly used antitumoural drugs, modulates microtubules, the biopolymers responsible for many essential cellular functions including cell division, movement and intracellular transport. This kind of drugs target tubulin subunits, the main microtubule proteins, and interfere with their dynamics, which can have the effect of stopping a cell cycle and can lead to programmed cell death or apoptosis.

Read more on the ALBA website 

Image: Microtubule X-ray fiber difractogram in presence of Paclitaxel.

Credit: NCD-SWEET beamline at ALBA Synchrotron

Accoustic spin waves: towards a new paradigm of on-chip communication

For the first time researchers have observed directly sound-driven spin waves (magnetoacoustic waves) and have revealed its nature.

Results show that these magnetization waves can go up to longer distances (up to centimeters) and have larger amplitudes than the commonly known spin waves. The study, published in Phys. Rev. Lett., is carried out by researchers from the University of Barcelona (UB), the Institute of Materials Science of Barcelona (ICMAB-CSIC), and the ALBA Synchrotron, in collaboration with the Paul-Drude-Institut in Berlin.

Researchers have observed directly and for the first time magnetoacoustic waves (sound-driven spin waves), which are considered as potential information carriers for novel computation schemes. These waves have been generated and observed on hybrid magnetic/piezoelectric devices. The experiments were designed by a collaboration between the University of Barcelona (UB), the Institute of Materials Science of Barcelona (ICMAB-CSIC) and the ALBA Synchrotron. The results show that magnetoacoustic waves can travel over long distances -up to centimeters- and have larger amplitudes than expected.

>Read more on the ALBA website

Image: TOP: A propagating and a standing magnetization wave in ferromagnetic Nickel, driven by magnetoelastic coupling to a surface acoustic wave in a piezoelectric LiNbO3substrate. The images combine line profiles (color indicating the local magnetization direction) at different delay times between the probing X-ray pulse and the electrical SAW excitation.
BOTTOM: Scheme of the strain caused by the surface acoustic waves (SAWs) in the piezoelectric (in green color scale) and magnetic modulation in the ferromagnetic material (in orange-cyan color scale).

Ten years at the service of the society and its challenges

On 22nd March 2010, ALBA was inaugurated becoming one of the most important scientific infrastructures of Spain.

Since then, its synchrotron light has been a great ally for numerous advances in a huge range of scientific fields, such as biomedicine, materials science, nanotechnology or archaeology. The ALBA Synchrotron represents a formidable return of knowledge, development and well-being for society.
Cerdanyola del Vallès, 23rd March 2020 10 years have passed since the inauguration of ALBA, the Spanish synchrotron light source. InMarch 2010, it was celebrated the launch of an unprecedented scientific project whose aim was becoming an essential tool for science and technology. Ten year later, ALBA has far exceeded its initial expectations, also being an international reference among worldwide light sources. It is currently under a continuous growth process byinstalling new equipment and updating its instrumentation to meet both present and future scientific challenges. In particular, ALBA is helping in the fight against COVID-19 to advance in the knowledge of the virus and in the development of vaccines and treatments.

The number of synchrotron light users in Spain has reach, from the initial 200 at the time of the project approval, to more than 5,000 users, almost half of them international; as well as more than 50 private national and international companies. In total, ALBA has provided synchrotron light for research groups belonging to 1,850 institutions from 45 different countries. The result has been more than 1,500 experiments performed that have been reflected in around 1,100 scientific publications.
Currently, the ALBA Synchrotron has 8 beamlines and 5 more are under construction, all equipped with different techniques for analyzing matter at an atomic and molecular level thanks to the high quality of the synchrotron light produced. Since the beginning, 37,722 hours of light have been generated. In this time, the electrons inside the accelerators would travel 2.7 million times the distance from Earth to the Sun!

>Read more on the ALBA website.

Imaging how anticancer compounds move inside the cells

Chemotherapeutics are key players in the clinical setting to fight most types of cancer, and novel chemicals hold the promise to facilitate new and unique intracellular interactions that modulate the cell machinery and destroy the tumour cells. Equally necessary are new tools that enable the unequivocal location and quantification of such molecules in the intracellular nano-space, so that their therapeutic action is fully understood.

Researchers from IMDEA Nanociencia, the ALBA Synchrotron, the European Synchrotron Radiation Facility (ESRF) and the National Centre for Biotechnology (CNB) have developed a new family of organo-iridium drug candidates about a hundred times more potent than the clinically used drug cisplatin.
In order to understand the therapeutic potential of the compound, it is mandatory to accurately localize its fate within the cell ultrastructure with minimal perturbation. To this aim researchers have correlated on the same cell, for the first time, two 3D X-ray imaging techniques with a resolution of tenths of nanometers: cryo soft X-ray tomography, at MISTRAL beamline at ALBA Synchrotron, and cryo X-ray fluorescence tomography, at ID16A beamline at ESRF. These techniques help elucidate the 3D architecture of the whole cell and to reveal the intracellular location of different atomic elements, respectively.

>Read more on the ALBA website

Comprehensive study of strontium hexaferrite platelets

Researchers have synthesized and studied by a combination of soft X-ray techniques platelets of strontium hexaferrite allowing them to establish the differences and similarities between their synthesized nanostructures and commercial powders.

Most of the experiments have been performed within a collaboration among three beamlines of the ALBA Synchrotron.
Ferrites are ceramic materials usually made of large proportions of iron oxide (Fe2O3, rust) blended with small proportions of other metallic elements. These materials do not conduct electricity because they are insulators; and they are ferromagnetic, which means they can easily be magnetized or attracted to a magnet.

Strontium ferrites (SFO, SrFe12O19) in particular have a large magnetocrystalline anisotropy that gives it a high coercitivity, meaning that it is difficult to demagnetize. Since its discovery in the mid-20th century, this hexagonal ferrite has become an increasingly important material both commercially and technologically, finding a variety of uses and applications because of its low cost and toxicity. SFO has been used for permanent magnets, recording media, in telecommunications, and as a component in microwave, high-frequency and magneto-optical devices. Also, because they can be powdered and formed easily, they are finding their applications into micro and nano-types systems such as biomarkers, bio diagnostics and biosensors.

>Read more on the ALBA website

New biocompatible nanoparticles for breast cancer therapy

A research team has studied the efficacy of new CHO/PA polymeric nanoparticles for the sustained delivery of a drug used in breast cancer therapy. Some of the experiments have been carried out in the NCD-SWEET beamline at ALBA.

According to data from the Spanish Association against Cancer (AECC) observatory, breast cancer is the second most common type of cancer in Spain with 33,307 new cases in 2019. The number of deceased has reached 6,689 this year. Many research groups are exploring new ways to fight against this disease.
Dasatinib, an FDA-approved compound for the treatment of chronic myeloid leukemia, has become a potential candidate for the treatment of other cancers. It has been recently demonstrated that it could have a relevant role in breast cancer therapy. However, the solubility of this compound is extremely low, leading to poor absorption by the organism. Thus, the administration of a higher dosage is needed in order to obtain a better effect.
An alternative solution to enhance its therapeutic effect is the development of polymeric nanoparticles for a sustained and controlled delivery of the drug.
>Read more on the ALBA website

Image: 2D SAXS and WAXS patterns of the CHO/PA nanoparticles recorded at NCD-SWEET beamline, which confirm the lack of well-structured mesophase.


The mechanism of the most commonly used antimalarial drugs unveiled

For centuries, quinoline has been an effective compound in antimalarial drugs, although no one knew its mode of action in vivo.

Today, a team led by the Weizmann Institute has discovered its mechanism in infected red blood cells in near-native conditions, by using the ESRF, Alba Synchrotron and BESSY. They publish their results in PNAS.

Malaria remains one of the biggest killers in low-income countries. Estimates of the number of deaths each year range from 450,000 to 720,000, with the majority of deaths happening in Africa. In the last two decades, the malaria parasite has evolved into drug-resistant strains. “Recently, the increasing geographical spread of the species, as well as resistant strains has concerned the scientific community, and in order to improve antimalarial drugs we need to know how they work precisely”, explains Sergey Kapishnikov, from the University of Copenhagen, in Denmark, and the Weizmann Institute, in Israel, and leader of the study.

Plasmodium parasite, when infecting a human, invades a red blood cell, where it ingests hemoglobin to grow and multiply. Hemoglobin releases then iron-containing heme molecules, which are toxic to the parasite. However, these molecules crystallise into hemozoin, a disposal product formed from the digestion of blood by the parasite that makes the molecules inert. For the parasite to survive, the rate at which the heme molecules are liberated must be slower or the same as the rate of hemozoin crystallization. Otherwise there would be an accumulation of the toxic heme within the parasite.

>Read more on the ESRF website

Image (taken from BESSY II article): The image shows details such as the vacuole of the parasites (colored in blue and green) inside an infected blood cell.
S. Kapishnikov

Two other institutes, BESSY II at HZB and ALBA Synchrotron, have participated in this research. Please find here their published articles:

> X-ray microscopy at BESSY II reveal how antimalaria-drugs might work

> The mechanism of the most commonly used antimlalarial drugs in near- native conditions unveiled

Gene encapsulation with MOFs for new delivery vectors in gene therapy

A research team from RMIT University, CSIRO Manufacturing, University of New South Wales, Graz University of Technology and the University of Adelaide, in Australia, have demonstrated an easy and efficient method to use nano MOFs for carrying large-size intact gene sets to be applied in gene therapy. Their study reports encapsulation of a complete gene-set in zeolitic imidazolate framework-8 (ZIF-8) MOFs and cellular expression of the gene delivered by the nano MOF composites, with data obtained at the MISTRAL beamline at the ALBA Synchrotron showing intracellular presence of the biocomposite particles.

MOFs (metal-organic frameworks) are porous materials with well-defined geometry and high loading capacity. For biological applications, their high porosity makes these composites an effective strategy for loading and protection of proteins; however, their use for other biomacromolecules such as nucleic acids is still in their infancy. Now, a research team lead by RMIT University from Melbourne has been studying the use of ZIF-8 MOFs as possible gene delivery vectors. The results show encapsulation of a gene-set in ZIF-8 MOFs and its cellular expression, proving that MOFs do not damage the structural and functional activity of the cargo nucleic acid, essential for possible applications in gene therapy as disease treatments.

>Read more on the ALBA website

Image: Left: Confocal laser scanning microscope images of plGFP@ZIF-8 transfected into human prostate cancer epithelial cells. See the entire image here.

A research, led by the ALBA Synchrotron and funded by the European project NANOCANCER, has analysed the impact of nanoparticles in radiotherapy of glioma tumour cells.

Combining radiotherapy with nanoparticles can increase the efficacy of cancer treatments. The experiment has been carried out at the MIRAS beamline of ALBA, devoted to infrared microspectroscopy.

The use of nanotechnology in medicine is nothing short of revolutionary. Nanosensors for diagnosis, nanoparticles for drug delivery or nanodevices that can regenerate damaged tissue are changing the way we face and treat several diseases.

Combining radiotherapy with nanoparticles is a promising strategy to increase the efficacy of cancer treatments. High-atomic number nanoparticles are used as tumour radiosensitizers: tumour cells previously loaded with nanoparticles enhance the radiation effects when exposed to radiotherapy. “It’s a kind of knock-on effect; the interaction of the radiation with the nanoparticles generates short-range secondary radiation that induces a local dose enhancement in the tumour cells. However, the mechanisms underlying the synergistic effects involved in these techniques are not clearly understood’, says Immaculada Martínez-Rovira, Marie Curie scientist of ALBA and expert in the development of innovative radiotherapy approaches.

>Read more on the ALBA website

Image: Researcher Imma Martínez-Rovira, Marie Curie scientist of ALBA and expert in the development of innovative radiotherapy approaches.

Synchrotron light for deciphering Friedreich’s Ataxia

A team from the Germans Trias i Pujol Research Institute (IGTP) in Badalona is performing an experiment at the ALBA Synchrotron to obtain for the first time 3D images of cells with this disease.

Friedreich’s ataxia affects more than 3,000 people in Spain, causing serious mobility problems and other severe illnesses such as heart disease. At present there is no treatment to prevent or cure the disease.

Friedreich’s ataxia is a rare neurodegenerative disease that progressively damages mobility, balance and coordination. It is an inherited disease, caused by a genetic mutation, that can appear when both parents are carriers. A research group from the Germans Trias i Pujol Research Institute (IGTP), at the Can Ruti Campus in Badalona, led by Dr. Antoni Matilla, is looking into the causes and possible treatments for this disease that results in high disability and an important decrease in the patients’ quality of life.

“Today there is no treatment or cure for Friedreich’s ataxia. It is necessary to try to understand how the disease develops in order to propose therapeutic solutions”, says Dr. Ivelisse Sánchez, co-Principal Investigator of this project at the Neurogenetics Unit of the IGTP. Researchers are now analysing donors’ cells in the ALBA Synchrotron to see the changes caused by the disease.

>Read more on the ALBA website

Image: Dr. Ivelisse Sánchez, co-Principal Investigator of the project, and pre-doctoral researcher Eudald Balagué at the MISTRAL beamline.

New method to get stable perovskite-based material for more efficient solar cells

Perovskites materials are promising candidates for next generation solar cells. However, their use is still limited by their instability within ambient conditions. Instead of absorbing all visible light and appearing black, some of these super materials preferentially form another structure which is yellow. Since only the black form is optically active, the current challenge is achieving stable black perovskites thin films suitable for real world optoelectronic devices. An international team of scientists, led by a group from KU Leuven in Belgium, have shone a light on this problem developing a new method to stabilize the black form introducing strain into the perovskite thin film using the glass substrate on which it sits. Synchrotron-based techniques at the ALBA Synchrotron and the European Synchrotron Radiation Facility were crucial for obtaining these results, published today in Science.

>Read more on the ALBA website

A step closer to smart catalysts for fuel generation

Researchers at the Universidade Federal do Rio Grande do Sul in Brazil in collaboration with the ALBA Synchrotron have performed the first detailed measurement of the strong metal-support interaction (SMSI) effect in Cu-Ni nanoparticles supported on cerium oxide.

A better understanding of this effect is essential for developing smart catalysts that are more selective, stable and sustainable. The quest for the best catalysts in industry has been a long one, but a new study by Universidade Federal do Rio Grande do Sul in Brazil, in collaboration with the ALBA Synchrotron, has come a step closer. For the first time, researchers have found evidence of what could be the origin of the SMSI effect in catalysts supported on cerium oxide.

Catalysts are used to increase the reaction rate of a given chemical reaction, and have applications in a wide variety of fields. In heterogeneous catalysis, the catalyst is usually composed of metal nanoparticles supported on metal oxides. Among them, CeO2-based catalysts have unique structural and atomic properties that make them suitable in the cutting-edge environmental industry of fuel cells and hydrogen. In this field, they are being explored as high-end photocatalytic reactors for the thermal splitting of water and carbon dioxide. However, what has been termed as the SMSI effect can undermine their desired properties.

>Read more on the ALBA website

Image: (extract, full picture here) Near Ambient Pressure – X-ray Photoemission Spectroscopy allowed the identification of the chemical components of the nanoparticles in situ.

X-rays find key insights in metal-oxide thin film interfaces

Researchers from the Institut de Ciència de Materials de Barcelona (ICMAB-CSIC) and ALBA Synchrotron have led a collaborative research, together with the Institut Català de Nanociència i Nanotecnologia (ICN2), the Dept. of Electronics and Biomedical Engineering (University of Barcelona) and CIC nanoGUNE (Donostia), where they have exploited X-ray absorption spectroscopy at the BOREAS beamline of ALBA for unveiling the optical and spin transport properties of transition metal oxides for photovoltaics and spintronics applications.
There is an urgent need of metallic and transparent electrodes for applications in advanced technologies such as flat panel displays or electrodes for photovoltaics, that may substitute the ubiquitous and exceedingly expensive and scarce Indium-Tin oxide (ITO). The AMO3 perovskites (being A an alkaline earth and M an early 3d transition metal, e.g. SrVO3) are driving attention because their intrinsic metallic character combines with the strong electron correlation within the narrow 3d band, to produce a material having its plasma frequency down to infrared and thus transparent at visible range.

>Read more on the ALBA website

Image: Illustration of different phenomena occurring at the interface between a ferromagnetic insulator and a heavy metal.

The interaction between two proteins involved in skin mechanical strength

A research team from the Centro de Investigación del Cáncer of the Universidad de Salamanca has obtained a detailed 3D image of the union between two hemidesmosomal proteins.

The structure of this complex has been unveiled using XALOC beamline techniques, at the ALBA Synchrotron. The results, published in “Structure”, provide insights to understand how these epithelial adhesion structures are formed. Researchers from Centro de Investigación del Cáncer – Instituto de Biología Molecular y Celular del Cáncer of Salamanca, from Centro Universitario de la Defensa in Zaragoza, and from the Netherlands Cancer Institute in Amsterdam have described how two essential proteins interact to each other in order to join epidermis and dermis together. This study reveals at atomic scale how the binding between two hemidesmosomal proteins called integrin α6β4 and BP230 takes place.
Epithelial tissues, such as epidermis, settle on fibrous sheets called basement membrane, formed by extracellular matrix proteins. The junction between epithelia and basement membrane happens through hemidesmosomes, multi-protein complexes located at the membrane of epithelial cells. Integrin α6β4 is an essential protein of the hemidesmosomes, which adheres to proteins of the basement membrane. Inside the cell cytoplasm, plectin and BP230 proteins bind to α6β4 and connect it to the intermediate filaments of the cytoskeleton. Genetic or autoimmune alterations that affect the hemidesmosomal proteins reduce skin resistance and cause diseases such as bullous pemphigoid and various types of epidermolysis bullosa.

>Read more on the ALBA website

Image: Structure of β4(WT)-BP230 complex.

Coherent scattering imaging of skyrmions

Profiting from the coherence of synchrotron light, scientists have performed both reciprocal and real-space observations of magnetic skyrmion lattice deformation in a chiral magnet Co8Zn8Mn4.

The study of these materials is key for developing futures spintronic applications such as racetrack memory and logic devices.
The interplay between exchange interaction, antisymmetric Dzyaloshinskii-Moriya interaction, and magnetocrystalline anisotropy may cause incommensurate spin phases such as helical, conical, and Bloch-type skyrmion lattice states. The typical size of a magnetic skyrmion varies in a range from a few to a few hundred nanometers which makes them promising candidates for future spintronic applications such as skyrmion racetrack memory – with storage density higher than solid-state memory devices- and logic devices.
Coherent soft X-ray scattering and imaging are powerful tools to study the spin ordering in multicomponent magnetic compounds with element selectivity.
In this experiment, a skyrmion-hosting compound Co8Zn8Mn4 was investigated at cryogenic temperatures and applied high magnetic fields by a group of researchers from the Japanese RIKEN Center of Emergent Matter Science, National Institute for Materials Science, the Science and Technology Agency, University of Tokyo, the Institute of Materials Structure Science and Photon Factory, as well as from the ALBA Synchrotron.

Image: Coherent soft x-ray speckle patterns measured for Co8Zn8Mn4 sample at L3 absorption edge of Co at different temperatures 150 K, 120 K, 25 K (top panel, left to right) and applied field of 70 mT. White scale bar corresponds to 0.05 nm−1. Bottom panel shows micromagnetic simulations of the corresponding skyrmionic spin textures.