The Soft Condensed Matter Group provides the infrared (IR) and Circular Dichroism (CD) spectroscopy and, both Small and Wide Angle X-ray Scattering (SAXS and WAXS) imaging capabilities of Diamond. The Soft Condensed Matter Group comprises of four beamlines B21, B22, I22 and B23. This unique portfolio of beamlines can analyse a range of samples that include two-dimensional thin films (photovoltaics), living mammalian cells, three-dimensional matrices (metal-organic frameworks) and nano-particles in non-crystalline states.
The Soft Condensed Matter Group maintains a dedicated laboratory space for our visiting users. The laboratory houses vital equipment for sample preparation and analysis such as a centrifuges, a small tissue-culture facility, spectroscopy equipment (including CD, standalone IR and UV spectroscopy, multi-angle and quasi-elastic light scattering) and the ability to work with different gases. Laboratory and offline instrumentation usage can be reserved through the User Administration System at any time throughout the operational year of Diamond. Since the start of 2017, both B21 and B23 now offer mail-in services for solution-state SAXS and CD measurements.
Operational since 2009, the Circular Dichroism beamline (B23) uses circularly polarised light to characterise the structure of complex materials in solution and in solid state films. Many molecular systems have a handedness (chirality) to them akin to our right and left hands. This molecular handedness will preferentially absorb light that is either right-polarised or left-polarised and at B23, measurements are made that precisely quantify how much of each type of light is absorbed by the sample. In thin films, quantification of the polarisation at micron resolution can inform on how materials prefer to orient themselves and for biological samples, CD spectra can be used to demonstrate conformational changes, drug binding or instabilities in a protein.
B23 has pioneered development of high-throughput screening (HTCD) and CD Imaging (CDi) technologies and most recently, the B23 team has developed a unique extreme-environment high pressure cell (HPC). The high pressure sample cell can withstand 2500 times atmospheric pressure while allowing researchers to measure the sample CD spectra. For the life sciences, this sample cell allows researchers to investigate the stability of proteins and enzymes in the solution state under extreme conditions.
The Multimode Infrared Imaging and Microspectroscopy (MIRIAM) beamline (B22) is used to assess the molecular composition and microscopic spatial distribution of a sample at the highest, optically-achievable resolution. B22 operates two end-stations that are dedicated to confocal infrared spectromicroscopy and IR imaging, with a suite of single and array detectors that cover the whole IR range. B22 is used for a wide variety of applications such as the analysis of inorganic-organic combinations and polymers, as well as studying live cells in situ.
The beamline is developing the novel use of adaptive optics to enable the highest contrast IR images in full field microscopy. The adaptive optics instrument uses an innovative double set of deformable mirrors for shaping the IR beam intensity profile. The multipixel detection and image oversampling aims to prove the ultimate spatial resolution and sensitivity achievable in IR imaging via synchrotron radiation. This unique instrumentation capability will be able to study inter-/intra-cellular structures, gas/liquid inclusions evolution in mineralogical sections driven by temperature, hyperspectral imaging of thin film/polymer interfaces, biofilms composition, microcrystal gas-solid reactions in situ, as well as catalysis dynamics in microfluidic devices.
The Small Angle Scattering and Diffraction beamline (I22) offers combined Small and Wide Angle X-ray Scattering studies (SAXS and WAXS) on a range of low order biological and synthetic samples. It is particularly adept at providing structural information on partially ordered materials ranging from bone and thin-films to large helical structures such as collagen.
I22 pioneered the first in-vacuum Pilatus 2M WAXS detector. Recent optimisations combining simultaneous SAXS and WAXS measurements have enabled measurements that cover a resolution range of nearly 10000. This resolution range can provide information at length scales from the size of a single bond to the width of a bacteria cell. This optimised X-ray camera generates a massive amount of data for Diamond users and I22 has also focused on integrated pipelines for data reduction and processing in the scientific software platform DAWN. In the coming year, I22 will be introducing an integrated microfocus capability allowing for rapid changes in beam sizes ideal for scanning experiments.
The High Throughput SAXS beamline (B21) is dedicated to the study of noncrystalline, randomly oriented particles. SAXS measurements can be made on any type of sample and in any physical state. For the life sciences community, solution state SAXS measurements allow for the opportunity to study biological machines in conditions that are comparable to their liquid, hydrated environment. This ability complements the many solid-state studies performed at Diamond using X-ray crystallography and cryo-electron microscopy. The B21 end-station can be configured for low-throughput, syringe-pump based experiments and high-throughput batch-mode experiments using either the bioSAXS sample delivery robot or high-performance liquid chromatography (HPLC) instrument for inline size-exclusion chromatography (SEC) coupled SAXS.
In the continued quest to lower the instrumentation background, B21 relocated the sample and detector downstream by nearly five metres (Fig. 2). This move, coupled with the recent optics upgrade, increased the operational flux at the sample position by nearly 21-fold with a comparable decrease in instrumentation background in the highest resolution region of the detector. This optimised sample position enabled further improvements in the SEC-SAXS sample cell reducing the exposed sample volume from 24 to 10 uL. The new configuration will be complemented by in-line multi-angle light scattering that will not only inform on the sample’s molecular mass but also, enable measurements at smaller scattering angles.
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