Small-angle X-ray Scattering Beamline Research Articles

The new small-angle X-ray scattering beamline for materials research at PETRA III: SAXSMAT beamline P62.

The SAXSMAT beamline P62 (Small-Angle X-ray Scattering beamline for Materials Research) is a new beamline at the high-energy storage ring PETRA III at DESY. This beamline is dedicated to combined small- and wide-angle X-ray scattering (SAXS/WAXS) techniques for both soft and hard condensed matter systems. It works mainly in transmission geometry. The beamline covers an energy range from 3.5 keV to 35.0 keV, which fulfills the requirements of the user community to perform anomalous scattering experiments. Mirrors are used to reduce the intensity of higher harmonics. Furthermore, the mirrors and 2D compound refracting lenses can focus the beam down to a few micrometres at the sample position. This option with the high photon flux enables also SAXS/WAXS tensor tomography experiments to be performed at this new beamline in a relatively short time. The first SAXS/WAXS pattern was collected in August 2021, while the first user experiment was carried out two months later. Since January 2022 the beamline has been in regular user operation mode. In this paper the beamline optics and the SAXS/WAXS instrument are described and two examples are briefly shown.

Reversible rearrangement of magnetic nanoparticles in solution studied using time-resolved SAXS method.

Superparamagnetic nanoparticles have broad applications in biology and medicines. Quantitative measurements of magnetic beads in solution are essential in gaining comprehensive understanding of their dynamics and developing applications. Here, using synchrotron X-ray sources combined with well controlled magnetic fields, the results from small-angle X-ray scattering (SAXS) experiments on superparamagnetic particles in solution under the influence of external magnetic fields are reported. The particles mostly remain in monodispersed states and the linear aggregates tend to be aligned with the external magnetic field. After removing the magnetic fields, the superparamagnetic nanoparticles quickly recover to their original states indicating high reversibility of the rearrangement under the control of a magnetic field. The external magnetic field instrument composed of paired permanent magnets is integrated into the SAXS beamline at the Shanghai Synchrotron Radiation Facility providing a platform for studying time-resolved dynamics induced by magnetic fields.

Improvement and Upgrade of Small-Angle X-ray Scattering Beamlines at the Photon Factory

Three small-angle X-ray scattering (SAXS) beamlines, BL-6A, BL-10C and new BL-15A2 are available at the Japanese synchrotron facility, Photon Factory (PF). We are recently improving and upgrading the SAXS beamlines at the PF in order to support new measurements and construct a high-throughput experimental system. BL-6A is a bending magnet beamline and the wavelength is fixed at 1.5 angstrom. This beamline had two detectors, PILAUS 300K (Dectris) for SAXS/GI-SAXS and PILATUS 100K (Dectris) for WAXD experiment, respectively, and the simultaneous measurement using these detectors are available. We installed a new experimental stage and replaced PILATUS 300K with PILATUS3 1M in this March. Therefore, the range of an applicable camera length spread to 0.25 ~ 2.5 m, and the detectable angle area expanded in the small-angle region. BL-10A is also a bending magnet beamline and the wavelength has been fixed at 1.488 angstrom. We replaced almost all the optical and experimental components of this beamline with new ones in this March. A fixed-exit double-crystal monochromator, a focusing mirror and a mirror bender were newly installed in this beamline. We will be able to change the energy from 6 to 14 keV. Although the photon flux at the sample position will not change after this upgrade, the area of the beam at the focal point will decrease to 40 % on the basis of the raytracing calculation. The camera length spread from 2 m to 3m in a new experimental stage with the camera tube. PILATUS3 2M and 200K (Dectris) were also installed as a detector. The commissioning will be started from this May, and the beamline will be re-opened from this June. In order to control all new devices and make the user-operation easier, we newly developed GUI software for the beamline control and the experiment. We are also developing the solution sample mixer and changer at BL-15A2 for the high-throughput Bio-SAXS measurement. We will present the current status of these beamline refurbishment.

Heterogeneous Seeding of a Prion Structure by a Generic Amyloid Form of the Fungal Prion-forming Domain HET-s(218–289)

The fungal prion-forming domain HET-s(218-289) forms infectious amyloid fibrils at physiological pH that were shown by solid-state NMR to be assemblies of a two-rung β-solenoid structure. Under acidic conditions, HET-s(218-289) has been shown to form amyloid fibrils that have very low infectivity in vivo, but structural information about these fibrils has been very limited. We show by x-ray fiber diffraction that the HET-s(218-289) fibrils formed under acidic conditions have a stacked β-sheet architecture commonly found in short amyloidogenic peptides and denatured protein aggregates. At physiological pH, stacked β-sheet fibrils nucleate the formation of the infectious β-solenoid prions in a process of heterogeneous seeding, but do so with kinetic profiles distinct from those of spontaneous or homogeneous (seeded with infectious β-solenoid fibrils) fibrillization. Several serial passages of stacked β-sheet-seeded solutions lead to fibrillization kinetics similar to homogeneously seeded solutions. Our results directly show that structural mutation can occur between substantially different amyloid architectures, lending credence to the suggestion that the processes of strain adaptation and crossing species barriers are facilitated by structural mutation.

Refurbishing of Small-Angle X-ray Scattering Beamline, BL-6A at the Photon Factory

BL-6A at the Photon Factory is new small-angle X-ray scattering beamline. The light source makes use of a bending magnet, and the available wavelength, monochromatized by a Johann type crystal monochromator, is fixed to 1.5 Å. Various kinds of detectors for SAXS and WAXS experiments are installed in BL-6A, and a SAXS/WAXS simultaneous measurement system was also constructed. This beamline is maintained to measure various samples, such as protein solutions, fibers, liquid crystals as well as solid state materials.

The Current Status of Small-angle X-ray Scattering Beamline at Diamond Light Source

構造解析の一つの手法として，小角散乱法は様々な研究分野において有用である．近年，特に構造生物学分野において，X線小角散乱法（SAXS）が短時間に多くの構造解析が行える可能性のある有用な手法として，見直され注目を集めている．イギリス国内唯一の放射光施設であるDiamond Light Sourceでは2007年の供用開始から1本のSAXSビームライン（non-crystalline diffraction beamline, I22）が稼働中で，さらにハイスループット測定を実施することを目的とし，HATSAXS beamline（highly automated throughput SAXS beamline, B21）が建設されている．本稿では，特にX線小角散乱法を利用したタンパク質分子の構造解析に関してあらためて簡単に紹介するとともに，Diamond Light SourceのSAXSビームラインについてB21の現状に重点を置き報告する．

2PT123 フォトンファクトリーの小角散乱ビームラインの現状(日本生物物理学会第50回年会(2012年度))

2PT123 フォトンファクトリーの小角散乱ビームラインの現状(日本生物物理学会第50回年会(2012年度))

3I1136 フォトンファクトリーにおけるX線小角散乱ビームラインの新設と高度化(3I 蛋白質_計測・解析の方法論1,日本生物物理学会第49回年会)

3I1136 フォトンファクトリーにおけるX線小角散乱ビームラインの新設と高度化(3I 蛋白質_計測・解析の方法論1,日本生物物理学会第49回年会)

Leather Structure Determination by Small-Angle X-ray Scattering (SAXS): Cross Sections of Ovine and Bovine Leather

SAXS has been applied to structural determination in leather. The SAXS beamline at the Australian Synchrotron provides 6 orders of magnitude dynamic range, enabling a rich source of structural information from scattering patterns of leather sections. SAXS patterns were recorded for q from 0.004 to 0.223 A(-1). Collagen d spacing varied across ovine leather sections from 63.8 nm in parts of the corium up to 64.6 nm in parts of the grain. The intensity of the collagen peak at q = 0.06 A(-1) varied by 1 order of magnitude across ovine leather sections with the high-intensity region in the corium and the low intensity in the grain. The degree of fiber orientation and the dispersion of the orientation has been quantified in leather. It is shown how the technique provides a wealth of useful information that may be used to characterize and compare leathers, skin, and connective tissue.

In situ evaluation of structural changes in poly(ester-urethanes) during shape-memory cycles

The relationship between shape-memory behavior and structure was studied using three series of poly(ester-urethanes) with varying amounts of hard segment. The materials were designed to display a three-phase structure consisting of a disperse phase of crystallites and hard domains embedded in an amorphous matrix based on soft segment. Structure and thermal properties of the resultant materials were investigated using techniques such as modulated differential scanning calorimetry (MDSC), dynamic mechanical analysis (DMA) and small angle X-ray scattering (SAXS). The results revealed morphological changes in the materials during a low temperature shape-memory cycle. To study shape recovery, a deformed specimen was evaluated on a heating stage mounted at the SAXS beamline. Furthermore, to study the effect of temperature during recovery, the specimens were subjected to different thermo-cycles. Under each set of conditions, the phase morphology and composition were investigated. Temporary shape was stored by the metastable structure formed during deformation. The recovery was triggered by the melting of crystallites and hydrogen bonding between hard domains. The recovery process was divided into three stages. Bulk incompatibility and entropic recovery determined the final polyurethane morphology.

BioXTAS RAW, a software program for high-throughput automated small-angle X-ray scattering data reduction and preliminary analysis

A fully open source software program for automated two-dimensional and one-dimensional data reduction and preliminary analysis of isotropic small-angle X-ray scattering (SAXS) data is presented. The program is freely distributed, following the open-source philosophy, and does not rely on any commercial software packages.BioXTAS RAWis a fully automated program that,viaan online feature, reads raw two-dimensional SAXS detector output files and processes and plots data as the data files are created during measurement sessions. The software handles all steps in the data reduction. This includes mask creation, radial averaging, error bar calculation, artifact removal, normalization andqcalibration. Further data reduction such as background subtraction and absolute intensity scaling is fast and easyviathe graphical user interface.BioXTAS RAWalso provides preliminary analysis of one-dimensional data in terms of the indirect Fourier transform using the objective Bayesian approach to obtain the pair-distance distribution function, PDDF, and is thereby a free and open-source alternative to existing PDDF estimation software. Apart from the TIFF input format, the program also accepts ASCII-format input files and is currently compatible with one-dimensional data files from SAXS beamlines at a number of synchrotron facilities.BioXTAS RAWis written in Python with C++ extensions.

Small-angle x-ray scattering station 4C2 BL of pohang accelerator laboratory for advance in Korean polymer science

There are two beamlines (BLs), 4C1 and 4C2, at the Pohang Accelerator Laboratory that are dedicated to small angle X-ray scattering (SAXS). The 4C1 BL was constructed in early 2000 and is open to public users, including both domestic and foreign researchers. In 2003, construction of the second SAXS BL, 4C2, was complete and commissioning and user support were started. The 4C2 BL uses the same bending magnet as its light source as the 4C1 BL. The 4C1 BL uses a synthetic double multilayer monochromator, whereas the 4C2 BL uses a Si(111) double crystal monochromator for both small angle and wide angle X-ray scattering. In the 4C2 BL, the collimating mirror is positioned behind the monochromator in order to enhance the beam flux and energy resolution. A toroidal focusing mirror is positioned in front of the monochromator to increase the beam flux and eliminate higher harmonics. The 4C2 BL also contains a digital cooled charge coupled detector, which has a wide dynamic range and good sensitivity to weak scattering, thereby making it suitable for a range of SAXS and wide angle X-ray scattering experiments. The general performance of the 4C2 BL was initially tested using standard samples and further confirmed by the experience of users during three years of operation. In addition, several grazing incidence X-ray scattering measurements were carried out at the 4C2 BL.

Apparatus for the simultaneous measurement of the X-ray absorption factor developed for a small-angle X-ray scattering beamline

A novel apparatus has been developed that enables the simultaneous determination of the absorption factor during measurement of small-angle X-ray scattering (SAXS) intensities of a sample. It was designed especially for the use of relatively low-energy X-rays at SAXS beamlines of synchrotron facilities. The X-ray intensity of transmittance is measured by a silicon PIN photodiode, which is implanted in a direct beamstop set in a vacuum chamber. Since the assembly transmits an attenuated direct beam to a detector during the scattering measurement, a zero-angle position can be monitored without additional operation. It was confirmed that the linearity between the signal from the photodiode and the intensity of X-rays is good and the photodiode is applicable for the desired purpose. For a performance test, the absorption factors of a supercritical fluid were measured with a wide density range.

Setup for in situ WAXS/SAXS studies of the formation and growth of Bi nanodroplets and the melting of Bi nanocrystals using synchrotron radiation

The setup was designed for in situ studies of structural transformations in materials at high temperatures. It makes possible simultaneous recording of wide-angle X-ray scattering (WAXS) and small-angle X-ray scattering (SAXS) spectra from room temperature up to 1000 °C. The setup was installed in the National Synchrotron Light Laboratory SAXS beamline. It was applied to in situ studies of several structural transformations such as the formation and growth of liquid Bi nanodroplets embedded in a B 2O 3–Na 2O glass and the melting of Bi nanocrystals dispersed in the same glass matrix.

The beamlines of ELETTRA and their application to structural biology.

Protein crystallographers are nowadays regular users of synchrotron radiation (SR) facilities for several applications. The goal of majority of users is simply to extract more accurate, higher resolution data from existing crystals; they use monochromatic radiation and the rotation method, in order to get a complete survey of the reciprocal space in a short time. In fact the brilliance of SR is essential, due to the weak scattering power of the samples, and because of their sensibility to radiation damage. Over the last few years, however, a general increase of interest for measurements at multiple wavelengths, which exploit the anomalous dispersion for the phase problem (multiwavelength anomalous diffraction--MAD), has generated the need of intense tuneable sources. For these applications, the emphasis is on accurate measurements of the small differences between the intensities of Bragg reflections at various energies across the absorption edge of an element present in the sample. The macromolecular diffraction beamline at ELETTRA, which is now running routinely since spring 1995, has been designed to provide a high flux--highly collimated tuneable X-rays source in the spectral range between 4 and 25 keV. The radiation source is the 57-pole wiggler, which delivers a very intense radiation up to 25 keV, and is shared and used simultaneously with the small angle X-ray scattering (SAXS) beamline. The front-end filter system has a cut-off energy at about 4 keV. The beamline optics consists of a pseudo-channel-cut double-crystal monochromator followed by a double focusing toroidal mirror. The tunability and the stability of the monochromator allows the user to perform MAD experiments, and for this purpose, a fluorescence probe for the exact calibration of the absorption edge is available on-line. The experimental station is based on an imaging plate area detector from MarResearch, with a sensible area of 345 mm in diameter. A cooled N2-stream is available to cool the sample crystal in order to reduce the radiation damage. SAXS is an experimental technique used to derive structural information about supra-molecular assemblies, amorphous materials and partly ordered systems (e.g. size and shape of large molecules). The high-flux SAXS beamline at ELETTRA is mainly intended for time-resolved studies on fast structural transitions in the sub-millisecond time region in solutions and in partly ordered systems, triggered by external or process parameters, with a SAXS resolution between 10 and 1400 A in real space. The source is the already mentioned 57-pole and the SAXS beamline accepts three discrete energies of its spectrum, namely 5.4, 8 and 16 keV. The beamline optics consists of a flat double-crystal monochromator and a double focusing toroidal mirror. A multi-purpose sample stage, movable along an optical table in order to optimise the sample to detect distance, allows to perform fast time-resolved relaxation studies based on temperature- or pressure-jumps as well as stopped flow experiments. Moreover, the users have option to install their own specialised sample surrounding equipment. The optimisation of the beamline with respect to high-flux and consequently high-flux density, allows to perform the following experiments: low contrast solution scattering, grazing incidence surface diffraction, micro-spot scanning, X-ray fluorescence analysis, time-resolved studies > or = 11 microseconds, simultaneous small- and wide-angle measurements on gels, liquid crystals, biopolymers, amorphous materials, muscles.

First performance assessment of the small-angle X-ray scattering beamline at ELETTRA.

The double-focusing high-flux wiggler beamline dedicated to small-angle X-ray scattering (SAXS) and wide-angle X-ray scattering (WAXS) at ELETTRA has gone into user operation recently. It has been designed specifically for time-resolved studies of non-crystalline and fibrous materials in the submillisecond time scale, and has been optimized for small-angle scattering measurements. An overview of the beamline status and of some representative results, highlighting the performance of the SAXS beamline, are given.

Sample environments and techniques combined with Small Angle X-ray Scattering

The number of synchrotron radiation-based Small Angle X-ray Scattering beamlines has increased considerably over the last decade. With the high X-ray flux and collimation of these beamlines it not only has become possible to perform time-resolved experiments on time scales down to the millisecond/frame range, but also it allows experimenters to utilise new sample environments and use simultaneous several experimental techniques on one sample. An overview of recent developments in this field is given.

The Small-Angle X-ray Scattering Beamline of the Brazilian Synchrotron Light Laboratory

This paper describes the small-angle scattering beamline built at the Brazilian Synchrotron Light Laboratory (LNLS). Vertical focusing of the synchrotron beam is achieved by an elastically bent gold-plated cylindrical mirror. An asymmetric cut curved triangle-shaped silicon single crystal (111 reflection) is used for monochromatization and horizontal focusing. The mirror, monochromator optics and 2θ arm were designed to cover the spectral range between 1.0 and 2.0 Å. Three slit sets, a secondary photon shutter, two beam monitors, filters and absorbers, a multi-sample holder, a vacuum path, a beam-stopper and a set of detectors are the basic components of the workstation. The stepping motors are equipped with specially designed encoders. All mechanical and pneumatic movements and detectors can be remotely controlled using a direct panel or a PC.